Although I could have a cool distributed.net home page, I don't.

I prefer to work on improving the client rather than design web pages.

RC5 cores are available if you wish to work on those.

This AMD K7 core is about 90% complete and uses a bizarre combination of ALU and MMX instructions.
Hopefully it will have an instruction count of about 250 clocks/key, maybe even less.

For those interested, some RC5 rates in the x86 range:

Processor     Clocks/key  keys/s/MHz
386/386SX         2030         490
386/386SX(SMC)   ~1350         740      (Latest self-modifying core.  Estimate only)
486/486SX         1015         980
486/486SX(SMC)     958        1040      (Latest self-modifying core)
Pentium            700        1430
AMD K6/K6-2/K6-3   610        1640
P4                 529        1890      (4 clock latency on rotate left!!!)
Pentium-MMX        485        2060
Celeron/PII/PIII   356        2800
AMD K5             310        3220
Athlon             282        3540

There is a javascript key rate calculator using these numbers.

Try looking at the main site for more interesting material.