The guys I used to fly to autoraces learned their lesson after the first
trip. Subsequent trips they brought along empty one-gallon anti-freeze
bottles.
Personally, I carry the piddle packs that contain the stuff used in
disposable diapers. $4 for a pack of three in the camping department at
KMart.

Paul kgyy wrote:
A friend told me a while back that that a couple of pilots purchased
every type of human relief container, and armed with prior consumption
of a gallon or so of coffee or tea, made a test flight and reported on
the pros/cons of each. I think this could be quite funny but have
never been able to find the article. Anybody know of the source?