FPGA that upgrades Amiga 500 custom chipset or allow internet browsing...

[Hattig]

The other thing I had in mind was a "Super I/O board". There are lots of little breakout boards made for microcontrollers that do some cool stuff. TCP/IP, MP3 players, WIFI etc. Many of these seem to use the SPI bus.

I believe SPI is planned (tentatively?) for the Vampire 500 or Vampire 1200.

And yes, you can get microcontrollers that run the entire TCP/IP stack internally as well as providing ethernet/wifi - which would take a huge load off the CPU in an Amiga.

[Hattig]

The FPGA Arcade and other stand-alone computers are interesting but they are really only WinUAE in hardware form and I wouldn't get the same 'feeling' I get from using my (enhanced classic).

I disagree, they're not software emulations running on a different OS dealing with non-50Hz/60Hz monitors, they're hardware simulations (or hardware re-implementations), and as such they should feel the same* as the original, especially if you use an original keyboard.

* depending on the quality of the FPGA core of course, but these are very mature for the Amiga these days.