The lyrics from that awful theme song to "Friends" told you everything you needed to know about the hit NBC comedy. "I'll be there for you/ Like I've been there before/ I'll be there for you/ 'Cuz you're there for me too."
 
All together now... "Awww..."
 
Ross, Rachel, Monica, Chandler and Phoebe (yes, I always forget Phoebe [NOTE: As a commenter notes, it was actually *Joey* I forgot. Sorry, Matt LeBlanc.]) *were* always there for each other, when they weren't sleeping with each other and dealing with the repercussions of sleeping with each other. "Friends" was a safe zone in which viewers could rely on the therapeutic powers of camaraderie to overcome any adversity and in which we could count on never hearing a single mention of *anything* related to the real world outside of this hermetically sealed bubble. [Oh and yes, at its best, "Friends" was a tremendously funny and effectively performed multi-camera comedy, one that would have made my Best of the '90s list.]
 
"Friends" ended its run in May of 2004. After a respectable mourning period, "It's Always Sunny in Philadelphia" premiered on FX in August of 2005 as almost the anti-"Friends."
 
Replace Central Perk with Paddy's Pub and you had a filthy petri dish that served as a breeding ground for the friendship between Mac, Dennis, Sweet Dee and Charlie, four chums united by the awareness that each one would throw the other under the bus given half the opportunity. Be there for each other? Perish the thought. The characters on "It's Always Sunny in Philadelphia" thrive on torturing, humiliating and denigrating each other. They find happiness in getting in the way of each other's happiness, which means that over the course of 50-plus episodes, they've never lacked for happiness.
 
I'm eventually going to have to split hairs over this. After all, I have at least five comedies (possibly two or three more depending on how open your definition of "comedy" is) ranked higher than "It's Always Sunny in Philadelphia." But while some of the decade's comedies may be more consistent or more artful or brainier, it's very possible that no show makes me laugh harder than "It's Always Sunny in Philadelphia."
 
[More on my choice as TV's No. 29 Best of the Decade after the break...]
 
The exact cost of the demo video shot by stars Charlie Day, Glenn Howerton and Rob McElhenney to sell "It's Always Sunny in Philadelphia" has been lost in the abyss of the hype machine, but whether it cost $200 or $85 or $5, nobody has every doubted the show's DIY aesthetic. "It's Always Sunny in Philadelphia" is rough and raw. Episodes often zip along without any kind of structured flow at all, occasionally feeling like loose assemblages of conversations between friends (which they probably are) and often coming in at 18 or 19 minutes in the early seasons, either because of budgetary concerns or because the gang said what they wanted to say and didn't feel like padding was required.
 
The main characters are coarse and willfully unlikable and they thrive in situations that accentuate of self-destructive they are and how happy they are to destroy each other. The characters are capable of achieving gonzo levels of despicableness and Day, Howerton, McElhenney and Kaitlin Olson have never shied from taking their performances to the necessary extremes. I'd point to the second season as a peak, citing Dennis and Dee's descent into crack addiction in "Dennis and Dee Go on Welfare" or the game of sexual one-upsmanship in "Mac Bangs Dennis' Mom" or Dee and Charlie's steroid-assisted boxing training in "Hundred Dollar Baby." Those three episodes aired on three consecutive weeks in the summer of 2006 and took "It's Always Sunny in Philadelphia" from cult favorite to a place as one of TV's best comedies.
 
[My own personal list of gonzo "It's Always Sunny in Philadelphia" moments would be Charlie-heavy. I'd include "Rock, Flag and Eagle" from "Charlie Goes America All Over Everybody's Ass," the informercial for kitten mittens, several appearances by Green Man, posing as a burnt out Vietnam vet to get free lapdances in "Charlie Gets Crippled," just about anything involving Nightman and Day Man and any time Charlie pretends to be a lawyer, utilizing a voice that can only be described as "Atticus Finch by way of Foghorn Leghorn." But with other characters, I'd include Mac's attempts to get retroactively molested in "Charlie Got Molested," Dennis' unfortunate resemblance to a sex offender in the appropriately titled "Dennis Looks Like a Registered Sex Offender," almost any moment from Dee's  tragic relationship with David Hornsby's Rickety Cricket and the awesomely grotesque work from Nate Mooney and Jimmi Simpson as the McPoyles.]
 
Danny DeVito joined the cast in Season Two and there's at least some dissension in the fan ranks as to whether DeVito's additional star power actually improved the series. My feeling is that DeVito has helped make the show's tone even coarser, which hasn't always been ideal, though the episode where his character was running a "Dear Hunter"-style Russian Roulette ring in the bar's basement was worth any annoyance I might have felt else where. 
 
But "It's Always Sunny in Philadelphia" isn't just about low-brow laughs. 
 
Well, it's *mostly* about low-brow laughs and an kind of enjoyably toxic friendship. But it's not just dumb luck that "It's Always Sunny" has drunkenly stumbled its way through many of central cultural debates of the decade.
 
Topicality isn't necessarily something that is required in a good comedy series. NBC's Must-See Thursday block used to include the glib, self-absorbed topicality of "Seinfeld," meshing with the intentional obliviousness of "Friends" and "Frasier." The current Thursday NBC comedies are more topical, albeit obliquely. A show like "South Park" may have its finger on the pulse, but that yields an uncomfortable back-and-forth between genuinely savvy episodes and "Aren't we clever for thinking that people on both sides of an issue are equally foolish?" naval-gazing.
 
In many ways, "It's Always Sunny" may be the most alert and damning show currently on TV. It's the zeitgeist as interpreted by idiots. Mac, Dennis, Sweet Dee and Charlie may be idiots, but their ability to read the headlines and take away only the potential for opportunism is uncanny. Over five seasons, the gang has attempted to get laid at abortion rallies, hoard oil, flip houses to exploit the mortgage crisis, scam the welfare system, make terrorist videos, stage a wrestling match to benefit the troops and found ways to profit off of underage drinking. Inspired by "Invincible" they attempted to try out for the Philadelphia Eagles, while "Fight Club" and "Million Dollar Baby" led them into pugilism. They've attempted to run for political office and briefly become Internet video sensations, plus they attempted to use the Philadelphia Phillies' 2008 World Series win as an excuse to get out of a parking ticket. 
 
I'm not trying to pick on "Friends," but did you ever get the impression that any of those guys ever read a newspaper or knew where CNN was on their dial? The gang on "It's Always Sunny" is tapped into the world around them -- sports, politics, economics, entertainment -- and, like so many of us, they manage to misinterpret or take the wrong lessons from absolutely everything they learn. Like I said, it's idiocy. But it's brilliant idiocy. 
 
In some ways, "It's Always Sunny" treats Big Issues similarly to another comedy that very nearly made my list, Comedy Central's "Strangers with Candy." Both shows simultaneously mock the idea that scripted TV should be a delivery mechanism for enlightenment and "after school special"-type education, while also mocking the stupidity of people who would be totally in the dark about current events if "Law & Order" didn't occasionally rip a story or two from the headlines. It's a formula that guarantees that "It's Always Sunny" won't run out of storylines any time soon.
 
While the characters on "Friends" mellowed and matured, pairing up and having babies, "It's Always Sunny" has resolutely refused to allow Mac, Dennis, Sweet Dee and Charlie any sort of personal growth at all. We're almost supposed to assume that between the events in each episode, the characters drink so much beer (or worse) that they forget that they should probably be hating each other by now. None of them show any signs of growing up or settling down. And how could they? Paddy's is generally empty, they live in ratty apartments and none of them are exactly in stable relationships as they head into their mid-30s. Fortunately, none of the characters is adverse to a good get-rich-quick scheme (like writing M. Night Shyamalan's next movie hit, a comeback vehicle for Dolph Lundgren) or to the next one-night stand (extricated by the D.E.N.N.I.S. System). It's a good life and there's no reason why it shouldn't continue on for another five seasons.
 
So "It's Always Sunny in Philadelphia" is No. 29 on my list of TV's Best of the Decade.
 
Up tomorrow? A sometimes tragic long-running cautionary tale about the value of being able to drive stick-shift.