@matigo Nah, I'm sticking with the x86 machines for desktop hardware. Still love the old PPC-based laptops though, but not for their computational prowess.
I am tempted by the first generation Mac Pro given the low purchase price and reasonable upgradability. Apparently I can shove a (for me) nearly new dedicated graphics card into it, as well as upgrade to 64GiB of RAM and dual quad-core Xeon processors.
I wouldn't mind a bit of that multi-threading performance goodness combined with the massive amounts of RAM. ?