Which reminds me...
Nasa scientists have found that 10 minutes of pogoing on a trampoline a day is the most efficient form of exercise available to man. (or something similar)
I am often to be found (god help me) reliving my youth on my 'rebounder' to the tunes of a lost generation. My knees, however, have not forgiven me since I mistakenly enjoyed a session to the strains of the Clash's 'greatest hits'.
It's an exercise regime I recommend to all aging punks, with one caveat; be careful with 'White Riot', it still packs a punch.