I like high-end 90s RISC servers. I mostly collect Sun, but also a little SGI. I don't like workstations, realtime graphics, or funny cases. But an Origin-2000 is an amazing piece of hardware. I have a few smaller SGIs (O2 & O200), only because it makes dealing with the big machine easier. (O2 is a nice install server, etc.)
Sun E3500s & E4000s, STK 9730.