Has anybody here worked with the Connection Machine or the Lisp Machine?
zbyszek: I worked with a CM (at EPCC in Edinburgh, Scotland) in the mid-nineties for a little bit.  I think we used CM Fortran -- basically Fortran 77 with extra knobs on for parallelism.  I remember it as being a pleasant experience.  The programming paradigm effectively hid details of the data decomposition and communications and allowed you to write parallel code in a fairly straightforward fashion.  It was also the first supercomputer I go on to, so that was pretty exciting.
At the time, the CM was already being eclipsed by the Cray T3D and YMP.
Some more ideosyncratic parallel machines I used a bit later were the APE 100 (from Alenia Spazio/Quadrics) and Fermilab's ACPMAPS, which was reminded me of the CM for programming, although I don't know if they were at all similar architecturally.