I was just at VCF Midwest this past weekend, and I can assure you I am on some of the lower echelons of people who know about niche hardware.

I do get to see and play with a lot of interesting systems, but for most of them, I only get to go just under surface-level. It's a lot different seeing someone who's reverse engineered every aspect of an IBM PC110, or someone who's restored an entire old mainframe that was in storage for years... or the group of people who built an entire functional telephone exchange with equipment spread over 50 years (including a cell network, a billing system, etc.).