Video Game Consoles/Peripherals in order of rarity

[AfroLH]

I don't know, maybe to play Sonic CD, Lunar, Snatcher, Popful Mail, and the other *Can'tSayThisOnTV*ing awesome games on it?

 

[zeturi]

Sonic CD FTW. Though I played it on PC, it was prolly my favorite sonic game.

 

[Twilight Wolf]

Don't diss the Digital Pictures games! Double Switch is badass, and the acting is hilarious. Sewer Shark is surprisingly fun, too.

Also, Sol-Feace and Silpheed. Addictive as Heck shoot-em-ups.

As for the Famicom Disk System on an NES, it's totally possible without taking it apart. I don't remember for sure how it was done, but I think the NES is put on top of the FDS, connected by the expansion port. Then the cart connector from the FDS is connected to the cart slot on the NES through a Game Genie. Something like that. It works, anyways.