[bryanthompson]

I'm actually typing this while my 12" powerbook sits on my lap, ftr.

http://www.timesonline.co.uk/article/0,,2-1395183,00.html

The combination of heat generated by the computers and the posture needed to balance the equipment on the lap leads to raised temperatures around the scrotum, a study has found. Past research shows that higher scrotal temperatures can damage sperm and affect fertility. And the introduction of new technology such as Bluetooth and infrared connections — which provide wireless links to the internet — has resulted in a growing number of men using the machines on their thighs rather than at a desk.

I like to think of it as an "additional feature" instead of a problem... I suppose any 20 year old guy would.