I was attracted to Bitcoin by many things, and included was the statement about its running in the background when the CPU was idle. I installed 0.3.0 in Ubuntu 64-bit Maverick Meerkat (10.10), and for long periods of time it pins the CPU at 100%, according to the Conky monitor.

As the original poster noted, it is impossible to do anything else while the CPU is captured.

My CPU is an AMD Athlon 64-bit 7550 Dual Core 2511 MHz 512 KB cache.

TT