I have fond memories of the SGI machines - workstation and larger - I worked on in the 1990s and early 2000s. Octanes, O2s, Origins, Indigos, and so on.
They were best-in-class for visualization, and when used with Stereographic Crystal Eyes hardware/glasses, 3D was awesome. We also rendered high-quality POV-Ray animations on an O2 in 1996, when the software was barely 5 years old!
My last big computing efforts were on a SGI Origin 2000 (R12000) in 2002, and the allure of that machine was being able to get 32 GB of shared RAM all to myself.