Forty years ago I had a Sinclair QL with an 8086 emulator. Because the Sinclair QL had preemptive multitasking, I could easily search memory for patterns, monitor locations, stop and start the emulation, or change memory programmatically and easily from the QDOS side. It was worlds easier than using a debugger, particularly since I didn't own an 8086 system.

I always thought it was a clever way to get insights in to software while it was running that wasn't available to people with 8086 systems, and it's interesting to see this idea so many years later.