Beepster
Heh. Charlie is defs my fave character (even more than Frank). He's just so stupid and the group has corrupted and abused him so badly it's sad but he's the only one with any kind of morality. I like it when he wigs out and puts them all in their place.
 
I think my favorite was the "Steak Scam" ep where he's rushing around making sure the bar doesn't get shuttered despite the bullsnizz the other guys are pulling.
 
Actually the whole "Charlie work" meme reminds me of when I worked as the filth cleaner upper at a bizarro film company.

Yeah the Charlie Work episode was amazing. All done in one continuous shot as well. I love the whole "slamming the stool" motif which made sense at the end when Dee sat on it. Also a classic line from Frank when Charlie asks him why he's covering himself in black paint: "I'm paintin' a shirt!" 

Beepster
And for bit part characters I'd go for Gail the Snail. I've always had a weird, unexplainable crush on that Rajskub chick (probably best known for playing "Chloe" on 24). I just find her interesting to look at and she's funny as all hell.
 
I actually just got turned on to Mr. Show with Bob and David which she was on for a while. Pretty funny stuff for a sketch comedy.
 
But back to Sunny... "Now you're just kind of mashing it".
 
lulz

It's interesting to go back to Taxi and watch De Vito at the start of his fame, when he was in his 30's. Louie DePalma was the framework for almost every character he's played since then. He's just such a naturally funny guy. I used to love in Taxi when he'd stare vacantly into space with his eyes ever so slightly crossed....