I have smoked my fair share of pot. My dad used to get me to smoke with him at like 2am, so we could both get some sleep.
I smoke now when I'm in such amounts of pain, that there's nothing else I can do. (I have no real painkillers.) It makes me want Raspberry Toaster Strudels (every damn time), and makes me want to just lay around and space out.
Because I smoke it so sparingly, it doesn't take much, but if I smoke too much (like I do with my sisters), I get that whole 'oh shit everyone is gonna know' paranoia going.
However, I have a friend who smokes weed every day, not /quite/ all day, but close (medical marijuana for his pain, and he grows his own as he lives in Cali). That mofo can still get so high he forgets what character he is, in the video game he's playing - when the character icon is on the screen. It never fails to amaze me (and make me jealous). But when things start to get sour, he will slam the snark/nasty hammer down - he's super reactive to that stuff.