You made my day...
Memories...
The thing about the VAX is probably a sacrilege - this was the system which brought 32-bit computing to the masses, after all... I started on a 730, well built but slow; then a few 750s, 780, 785 and ended with 8800 (and some 4000 as far as I remember). And also a few MicroVAXen, had one beside my desk, real object of pride (it was actually a VAXstation).
The Rainbow wasn't *that* bad when it arrived - comparing to the other similar pieces of crap we had at the time; one could run either CP/M or PC/DOS, but what killed it for us was the weird pre-formatted floppies we had to use. Anyway, I think we had only two of these.
You've missed the Professional 350 and 380 workstations - again something to behold... The 8800 VAX I worked with had one of these as its console... still remember how to turn the VAX on - wellm the command was 'POWER ON', given at the console prompt of the Professional ... all the fans then came together...
To this list I'd add a few 11/40s, a single 11/45 and several 11/70s, which I liked a lot. Got my first UNIX on one of these, although don't remember the exact edition.
As far as the PDP-15, at one stage I was about to start doing my master thesis (in interactive computer graphics, that was 1980...) on one of these - actually an XVM - so I went through the manuals and especially the assembly, but was lucky - the machine was deemed too sensitive for a student to use (it was used to design PCBs at the time), so my experience with these is nowadays limited to playing with SIMH - still have a few virtual machines running DOS/15. The master thesis had to be done on an early HP - 2637A, called "Intelligent Terminal" - had to program a lot of linear algebra, matrix analysis and differential geometry to get the thing running - in BASIC...
SIMH is also what I run when I want to remember the VMS days (the VAX machine running under OpenSolaris on a quad-Opteron is faster than anything I've seen in metal...). As far as the LISP machine mentioned, I got the interpreter running on a SIMH PDP-1 machine - weird... computes the S-exp after you close the bracket, no returns.
Memories...