I tend to call he/she/it an assclown...or if I'm dying alot by the same thing its a 'for fuck sake'.
Other insults thrown at the TV/Computer include:
-Normal insults like bastard, ****, asshole biscuit, ************ etc
-'You cheap little monkey turd'
-'Hmph...at least I have chicken *eats a piece of chicken*'
-'DAMN CAT!' (when my cat decides my keyboard makes a good bed)
-'Right...not playing this now' Followed by logging off whatever it is, and then going back 5 minutes later to play some more, muttering under my breath about how I'm not sure why I still play the damn thing.
Slightly off topic, but when I'm fighting a particular person (NPC or another player) and they won't die, I say 'Your dead already, just have the common decency to stay still and let me finish killing you.'
At least I'm past the stage of throwing actual objects at the TV now....I broke one and learned my lesson...fucking expensive bastards to replace.