I am so glad someone mentioned those things. I told a few people about them a couple of months ago and was greeted by hails of derision because they all reckoned that a plastic bottle would do just fine.
Please tell us more about the Glastonbury accident.
This reminds me of the V Festival in 2004. Primal Scream were on in a tent in which there were no toilets. There was a capacity limit on the tent, and we were fortunate to be in before it got full.
One of my mates tried to go outside to have a slash, and asked the bouncer on the flap if it was okay for him to get back inside. The bouncer said, "It'll cost you." My mate came back in and told us, at which point we formulated a plan.
Beer was served in those McDonald's style paper cups, so we created a system involving everyone forming a circle with their backs to the slasher while he slashed into such a cup.
We even had a contest for who had the biggest wee, which I won with a pint and a half.