Does anyone know whether BeOS 5.03 Pro and/or any of its predecessors were compatible with the Cyrix brand of processor, particularly the Cyrix 366Mhz MII? Also, how well (if at all) will Haiku function on such a low-end CPU?
R5 works on any fully 586 compatible Cyrix, including the MII.
Sweet! We often forget about legacy hardware, especially when new components become less expensive. I always saw it as a waste. Since R5 will run on a Cyrix CPU, I can have some satisfaction in extending the useful life of my old Protek PC 
I’ve run Be as a media server platform or full OS on hardware I’ve bought for as cheap as $2.35 per unit that ran Cyrix MII’s. It’s incredible what you can do with Be and old hardware because of Be’s modular design. Just set up a partition or even a file folder to use to make images off of and start adding and/or subtracting until you get the best ratio of size to functionality you can for what you want to do. It really isn’t hard at all, much easier than anything I ever tried using Linux.
Then, depending on the hardware you want to use, you can install it on a regular desktop HDD, a 2.5" laptop HDD, or a CF card and CF/IDE adapter. You can find the CF/IDE adapters for as cheap as $2.50 apiece with a bit of looking.
Now I’m just waiting for the kernel so I can start moving everything over to Haiku!
DLazlo