Zontar‘s Mega Swirl is a fan adaptation of Sega Swirl, a puzzle game initially released in 1999. It’s basically samegame (those bubble-popping games you can get on the app store) with variations on the Dreamcast logo as game pieces.

20130710_mega_swirl_v0.1.0b_(genesis_game)

http://gendev.spritesmind.net/forum/viewtopic.php?t=1486