Slurred typing ("alfdkja;lsdfjk" or "cdlackg" instead of "clocks").
Invention of new vocabulary.
Being amused easily and quickly by thinks that would not normally be deemed as funny.
Loss of hand-keyboard coordination
i_love_sarah: what the hell?
flola1337: AHAHAHAHAHAHAHAHAHAHAHAHAHAAH LOLZ ROFL
flola1337: i think you have midnightis, sarah.