Actually, Leonard is a grade A asshole. All he does is stay hunched over making hate-filled, snide remarks about everyone around him if they don't have a pair of tits. Galecki himself doesn't come across much better in interviews either, at least to me.
I'm not sure we're watching the same show, because I don't see that at all. Granted Leonard is far from my favorite character, but he's no asshole. I know a few 'grade A assholes' and even consider one of them my friend, and Leonard is nothing like them. What I think gets mistaken for snide or hate filled comments, is just friends giving each other a hard time. I do it to my friends and they do it right back.
I don't know. That stunt he pulled on Raj last night--"Tell the new girl all about your work."--was pretty sadistic. He pretty much set Raj up to humiliate himself, just for the fun of torturing him a little.

). Penny obviously makes much less than this, probably around $25,000 a year. That's a little over $2,000 a month, which realistically probably isn't enough to afford the rent/bills/etc. for the apartment she lives in. If you think of her apartment as a one bedroom its a little more believable. The bigger question, though, is why Leonard and Sheldon have decided to live in the building when they could afford to buy homes or at least live separately (or share a bigger apartment). It must have to do with reasons other than money. Maybe they've mentioned it on the show and I don't remember. Even with all their spending on comics, I'm sure they both have a lot of money saved up.