Closest I have personal experience with, is the Alpha Micro AM100 S-100 processor that used the WD-16 aka MCP1600 chipset (LSI-11 chipset but different microcode). It is not a PDP-11 but lemme tell you, every time I see the WD chips on an AM100 CPU board it screams out "coulda been a LSI-11" to me. Working at the problem the other way: I remember a very early IMSAI product, was some sort of Unibus-to-S-100-interface. Never saw one in the flesh but it was in the IMSAI price lists. I think it was some sort of shared memory but maybe it was more than that (DMA? Doubt it but it would be nice.) Are the early IMSAI marketing docs up on the net anywhere? I think a lot of the mini-oriented stuff they listed early on (e.g. 14" SMD drive systems, 9-track systems) were vaporware but I could be proven wrong. Right now I can't even find the price lists on the net. Tim.