I can add a couple of anecdotes to this erudite thread.

One was the pilot who plumbed himself in to the glider pee tube using a
self-adhesive condom, and then forgot when he got out in a hurry to clear
the runway. He got a sharp reminder.
The other was the pilot who tried to mechanise the process, and tried a
lash-up in his bathroom, using a car windscreen washer pump, battery, and
one of those shower attachments that you push onto a tap. He found that he
was getting sucked in, couldn't reach to
switch off, and had to call his wife in to help. What questions she asked
have not been recorded.
So be careful.
Dave


At 00:57 26 December 2008, harold wrote:
For many of us soaring cross country pilots the condom catheter and a
leg bag are essential parts of a successful flight. David Sedaris has
a different take on the product. He's hilarious.
http://www.youtube.com/watch?v=YBdymtyXt8Y