"Distributed, shared memory" isn't what I saw of "grid computing". That mostly seemed to be driven by people who didn't understand distributed computing -- with some exceptions like Inferno -- particularly with Globus. People slapped "grid" on anything they could get away with, though. However, distributed shared memory (or the illusion of it) for compute systems does date from the 90s, at least in Global Arrays, and is going somewhat strong in various PGAS systems, including GA.
Kerrighed was an SSI system that actually was actually commercialized, apparently unsuccessfully. Current (I think) proprietary software systems in that sort of space are ScaleMP and Bproc (from Penguin Computing?). Dolphin had an SCI-based hardware solution for gluing together distributed systems, at least until recently. The Plan 9-ish Xcpu service was described as building on work with Bproc, but explicitly wasn't SSI.
Kerrighed was an SSI system that actually was actually commercialized, apparently unsuccessfully. Current (I think) proprietary software systems in that sort of space are ScaleMP and Bproc (from Penguin Computing?). Dolphin had an SCI-based hardware solution for gluing together distributed systems, at least until recently. The Plan 9-ish Xcpu service was described as building on work with Bproc, but explicitly wasn't SSI.