Maybe old news for some but if you were unaware there were a few modifications for the super nintendo that will allow you to play games from other countrys, switch 50/60 (pal/ntsc) among other things.
I have done all of these mods personally and can say that if you have decent soldering / hardware skills that they most are pretty easy.
First off is region locking. While this is common knowledge from years of game repair, lucky for us the only difference in reguards to US/JPN games is different sized cartridges. The easy way around that is to take a pair of plyers and remove the two pieces that are located inside the cartridge slot.
50/60 Pal/Ntsc Modification
Graphics and 50/60 mod provided by Gamesx
Another pretty cool Snes mod (if you play emulators on the pc) is the USB Snes Controllers. Check out a current list of USB compatables SNES hardware - here (they do usb for almost every other system as well) :icon_wink