Run these from a 16-bit MS-DOS environment. Many of them cannot be exited without rebooting the computer.
BWWILD - Pokémon Black & White: Wild Pokémon Battle
DPPOKBAT - Pokémon Diamond & Pearl: Trainer Battle
NYANCAT - Nyan Cat/Nyanyanyanyanyanyanya!
RIVALFUL - Pokémon Black & White: Rival Battle (3 tracks—play on 3 computers at the same time)
WANTGONE - Portal 2: Want You Gone
WNTRWRAP - My Little Pony Friendship Is Magic: Winter Wrap Up