Reproduction cartridges of the newly discovered prototype will retail for $100.
'Faceball 2000' was a popular title for both the Game Boy and SNES, which lead to the production of a prototype Virtual Boy version that never saw release. After a prototype cartridge resurfaced over at Planet Virtual Boy, that community of enthusiasts sought to make 'NikoChan Battle' aka 'Faceball,' available to Virtual Boy players the world over.
From Planet Virtual Boy, "To make a long and twisted story short: an about 80% complete prototype of the game has been in private hands for many years, but last September, everything changed when detailed descriptions of said prototype had been posted on our forum by Japanese 'Mr. G'.
"A bit later, the prototype had found its way into the hands of Virtual Boy enthusiast and PVB member bigmak, who has successfully dumped the cartridge by now and is going to release the ROM for free later this year! To recoup a part of the five-figure(!) sum spent to make all this possible, a special fundraiser is going to happen soon, in which people will have a chance to show their support for bigmak and receive complete, boxed reproduction copies of the game in return!"
Source: Planet Virtual Boy via Joystiq