Retro Treasures featured the rare beauty that is Sega's SC-3000 home micro only once, and that was ages ago, which apparently is a shame. The SC-3000 is a beautiful, rare, unique and very collectible Sega computer. It was released in 1983 and sold mainly to Japan, Australia and New Zealand, was based on the Master System's console daddy, sported some impressive for the time graphics and many excellent games. You can find out more about the SC-3000 here and you can try an emulator for the thing here.
In order to own the actual machine, you can try a certain -particularly impressive- Sega SC-3000 auction @ eBay. You will not only be bidding on a mint condition, boxed, home-micro, but also on the very rare Super Control Station, the equally rare Sega modem, a data cassette player, 8 cartridges and 3 games on tape. Seller ships worldwide.