An obscure, rare and quite wonderful beast, the oddly named and reassuringly cartridge-based Epoch Super Cassettevision was released in 1984 as the successor to the original Cassettevision. The console had 16K of video RAM and thus a palette of 512 colours, could handle up to 128 sprites, came with a RGB output and had roughly 30 games produced for it. Apparently, the Super Cassettevision was particularly good at shmups and arcade games.
Intrigued? Good, for you can grab a working, boxed console via this Epoch Super Cassettevision eBay auction. It is the Japanese NTSC version of the thing and comes with two controllers, power adapter and RF thingy.
Seller ships worldwide.