So the other day I found out where toasty comes from

[igotrhythm]

it's from friggin' Mortal Kombat

Originally Posted by Game Informer

Though he might not be as recognizable by his proper name, Dan Forden is know to gamers everywhere as "the toasty guy." After a particularly brutal uppercut, a digitized Forden quickly slides in to say "toasty!" The phrase originated as an inside joke during development, but Forden's smiling face and hilarious falsetto are now among Mortal Kombat's most recognizable signatures.

(from NoobFeed)