The plan was foiled by a technical problem, but it looks like eventually, someone might try to jump from 40km and apparently come close to reaching(or surpassing) the speed of sound. I assume theres less friction higher up because lower down friction limits free fall speed to around 300km/h
http://news.bbc.co.uk/2/hi/science/nature/2241175.stm
By the Way, can anyone explain why he breaths nitrogen (in or out or something) before making hisn ascention?