As far as I can understand no one gets sued over using 8bit samples. But something to be cautious about is using melodies that are still being put in games franchises today. So the theme from Legend of Zelda is out because Nintendo still uses it.
It seems any arcade game from the early 80's is cool - but the safest bet is to just stick to sound effects and leave the melodies alone.

plus if you're a chiptune artist an your writing songs just using the melodies from other themes, then, it puts you to shame in yourself that your stealin and cant think of anythin yourself. i mean ye, i used themes, but when im actually makin a theme of a game, like kirby or megaman. your right though, and aswell because most songs use other songs in them, but because they're not big, no one cares, no money is involved. is pretty ridiculous you are right bruv.

Just to clarify, this post was in respect to our remix competitions where BotBrs upload samples.

oh. well i feel stupid now.

well that's silly :D

We are all silly!

pff.. you all are so silly