What is *nosebleed*?
The result of over-excitement, especially when related to something "geeky" or tech-oriented. Often used in a sarcastic context.
Literal: OHMYGAWDYOUGUYS! I hacked my TI-86 to display linux commands instead of displaying the logarithm of 1337!! *nosebleed*
Sarcastic: Jesus Christ. The two new kids in study hall are so fucking annoying. Their conversations entirely consist of statements such as "OHMIGAWDS! HALO 3! *nosebleed*"
when a nerd see something hot that they cant comprehend like a naked girl on a cam or just get over excited about something dumb on the computer and the blood rush to there head
OHMYGAWD she's takin her bra off *nosebleed*