The!Cart is a very versatile flash cart for the Atari 8bit computers. It's main features are:
128MB (yes, megabytes) of flash and 512k of RAM
It can emulate more than 30 different cartridge types (standard 8/16k carts, Mega/XEGS/Atarimax switchable carts etc)
Optional PC-based software to manage flash cart contents
Incremental flash update function
The!Cart is a co-production between Wolfram "mega-hz" Fischer (original idea, PCB design and manufacturing), Peter "JAC!" Dell (PC software, nice entry selection on Atari) and me (CPLD logic, expert mode cartridge selection menu on Atari, flasher implementation and flash file format design).
The source code and binaries for the CPLD logic, the flasher and expert menu are available here.
The PC based "The!Cart Studio" software (which usually includes my latest Atari software updates) are available on Peter's website
More detailled information and pictures are available on Wolfram's website