Here's my attempt at a Universal Boot Cartridge for the N64.

Laugh as you may, it works. You can insert the cartidge with whatever save you want in the slot and use the switch to choose a boot chip to use. Currently it only supports CIC-6102 and CIC-6103.
If you want to do this yourself, you should know that you can connect all of the CICs together, they only need: To switch between CICs you only need to deny ground (pin 13) to those that shouldn't be active. If you just switch VCC (pin 16) the "inactive" ones still mess up the operation of the others.
I also observed that you can change the CIC at any point during execution of the game, and even reset it, the proper chip is only needed at initial power on (which is why cold reset is suppiled, eh?) though one of the CICs must be connected at all times.
All pinouts were figured out by Valery

A while ago the original (shown above) fell apart due to my miserable soldering job. I recently rebuilt it from my GameShark, though.
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