Six dual-core PandaBoard ES boards stuck in a wooden dish-drying rack :) One of these draws a max of 5-6 watts under heavy load, so the whole "rack" should stay around 30 watts during cluster benchmarking etc. It's not completely assembled yet so there are no real numbers. Total cost about $1500.
I was seriously considering trying something like this with either the Raspberry Pi or the APC <http://apc.io/>.
It looks like one PandaBoard can roughly match the CPU horsepower of four APC boards at a slightly lower price, so that's good to know. The Raspberry Pi might still beat out the PandaBoard in terms of purchase cost-to-Megahertz ratio. We'll see. :-)
Don't just look at MHz/$. The Raspberry Pi has a ARM v6 compatible core vs the PandaBoard which has a v7-A core, i.e., Raspberry Pi MHz < PandaBoard MHz.
Do you know of anyplace that quantifies the actual performance difference of the different ARM versions? Just want to see the general improvement jump over time
