Bitcoin Mining Rigs

The early Bitcoin miner was very efficient on electricity, however zero Bitcoin yield.

Leveraging multiple graphics cards. Will probably spend more money on electricity than getting ROI from mined Bitcoins.

8-core FPGA is probably better than the computer above but will likely spend more money on electricity than getting ROI from mined Bitcoins.

A computing center with specialized ASIC based Bitcoin mining capability will beat the above but will have to content with competing computing centers and mining pools.

See related pages on Bitcoin Money and Bitcoin Mining.