Funnily enough, new AMD29050 are still being made (maybe even with further development) by Honeywell - they form the basis of their range of avionics computers like Flight Management Systems etc.

The 29k was a pretty rad architecture, indeed. The CPU register file had 128 local registers and more than 64 global registers as well as two program counters, to start off with. Local registers could also be accessed indirectly. At a time of the register starved mainstream x86 architecture, it felt like rolling in gold and shrieking like a little piglet in ecstasy.