Bleemcast is the lesser known Dreamcast version of the Playstation emulator Bleem! originally for PC.
Bleemcast functioned very differently than Bleem! for PC. Bleem was one disc that allowed you to place (almost) any Playstation game into your PC and play it. Bleemcast, on the other hand, worked on a game-by-game basis. You would purchase a Bleempak of a certain game, and load that disc into your Dreamcast. When prompted, you swapped in your corresponding Playstation disc. You had to purchase a Bleempak for each Playstation game you wished to emulate. This was a necessity, not just an attempt to make money. To run well on Dreamcast, the emulator had to be hand-optimized for each specific game, as the Dreamcast had less horsepower than the computers of the day. The work paid off, however. The emulated games ran well on Dreamcast and even featured full screen anti-aliasing, support for the Dreamcast VGA box, and 640x480 output.
Due to pressure from Sony, Bleem was shut down in 2001. Only a handful of Bleempaks were released. The 3 Bleempaks released before Bleem closed their doors are: