I'm working towards my Ph.D. in computer engineering right now, and need to so some sort of VLSI project for one of my graduate courses. I've tasked myself with implementing a working clone of the GSU/SuperFX in Verilog. This could be used in future to allow greater compatibility for sd2snes, and maybe allow for cheap reproduction carts (depending on the size of the resulting logic).
There are others working on GSU (Graphics Support Unit) solutions for sd2snes as well, check this forum topic over at krikzz.com for more info. Thanks goes to SmokeMonster for the heads up.