The risk is that you'll pay more in the electricity bill than you'd get for what you mined. You'd be competing against a crowd that is a step ahead (FPGA) and a

The risk is that you'll pay more in the electricity bill than you'd get for what you mined. You'd be competing against a crowd that is a step ahead (FPGA) and a few early birds two steps ahead (ASIC). So better first check the current calculations. I checked a few days ago and it seemed that my 2011 MBP would earn me a few cents per day...