I've been on a bit of a rabbit hole with Digital Research in the last few days, specifically because I am utterly fascinated with Concurrent DOS.

I played with Concurrent DOS (and later MultiUser DOS) in PCem and I was utterly amazed. I hadn't realized that there was a preemptive multitasking operating system available to consumers as early as the mid 80's outside of AmigaOS.

I read the Wikipedia and I kind of understand why it didn't catch on, but man I kind of wish DRI (and Gary Kildall) was still around. I suspect if they were, they would have continued to make stuff that was at least interesting.