Super Nintendo

To run homebrew or ROMs on your SNES you'll need a flashcart.

For the SNES you'll want to decide whether or not you would like support for enhancement chips, if you would like them, the SD2SNES can support most, however, it will cost more (roughly double) the price of the Super Everdrive, a flashcart that only supports games with DSP chip games (only with a DSP chip soldered in).

If you aren't sure which games have which chips, you can check here:

http://en.wikipedia.org/wiki/List_of_Super_NES_enhancement_chips

If a game isn't listed, it doesn't have any special requirements to be played.

SD2SNES
If you'd like support for (some) enhancement games, you can get the SD2SNES, an open source flashcart.

Here is a (in)compatibility list for the SD2SNES:

https://sd2snes.de/blog/compatibility

Many of these games are within reach of the hardware, and have just not been implimented yet, for updates, you can check here:

https://sd2snes.de/blog/

And for a feature list what's planned:

https://sd2snes.de/blog/status

If you are interested, and would like to contribute to the project, you can do so here:

https://github.com/mrehkopf/sd2snes

Super Everdrive
If you would prefer a flashcart without support for enhancement chips outside DSP, you'll want to get the Super Everdrive. If you still want to play DSP chip games, you can solder it in yourself or pay to have one presoldered, however, this will increase the price by about $20.

Resellers
https://sd2snes.de/blog/shop-list

http://shop.krikzz.com/aboutus.sc