Freelove Freeway - Before Michael Scott there was David Brent, and though not as goofy as Michael Scott, the original boss of "The Office" was just as (if not a bit more) funny.   His opus, "Freelove Freeway" was performed during an episode where the staff must undergo customer service training.  With the entire staff being bored to tears, Brent whips out a guitar and begins to "entertain" the employees.  The song was later re-recorded for real with Oasis' Noel Gallagher, but if you ask me, nothing beats the original. 

Smelly Cat - Back when "Friends" ruled the ratings there was one song everyone was talking about.  No, not the awful theme song for the show which is seared into my brain like a common cattle brand.  I'm talking, of course, about Lisa Kudrow's folksy tribute to a stinking feline.  I remember  the day after this episode aired I heard people humming it all day and even though I don't think it's as funny as, say, every other song on this list, you have to give points for tenacity.

Werwolf Bar-Mitzvah - "30 Rock" has always been chock full of laugh-out-loud moments, but this one, musically, takes the cake.  Tracy Jordan, the show-within-a-show's ghetto-fab leading man (played by Tracy Morgan), makes a casual reference to a novelty single he had recorded some time ago and then, almost as quick as the wit of  the show's writers, we smash cut to a tiny snippet of that novelty single.  You can hear a full version as well here.   Please, if you're doing so already, watch "30 Rock."  Please!  Don't let  it go the way of "Arrested Development."  

Day Man - "It's Always Sunny In Philadelphia"  is one of my favorite shows.  it revolves around the horrible lives of five horrible people who own a crappy bar in a crappy part of Philadelphia.  Many episodes revolve around the gang, as they're referred to, hatching plans to get rich, get laid or get revenge on each other.  One episode - perhaps their most famous - centers around the idea that starting a band is the way to fame, fortune and women.  Fragments of the cast attempt to start different bands and the episode culminates with a performance by Charlie and Dennis, playing under the name Electric Dream Machine.  But funnier than the final scene is watching how the song came together. 

South Park Theme Song - "South Park" has always been a show fond of pushing buttons and testing the limits of what they could get away with.  Their theme song is no different.  It's all fairly cheery and fun until it gets to Kenny's lines.  What you can't totally hear him say is something I can't totally write down here, but suffice to say it involves liking girls with "big, big t*****s" and "big v*****s."  To get away with that on TV is worthy of a spot on this list.