I’ve spent the last couple weeks writing a window system for the VS100. I stole a fair amount of code from W, surrounded it with an asynchronous rather than a synchronous interface, and called it X. Overall performance appears to be about twice that of W. The code seems fairly solid at this point, although there are still some deficiencies to be fixed up.
The original mailing list announcement of the Linux kernel gets regurgitated quite often, but I had never seen the original announcement for X. Fascinating.