My weekly scour for all things "back of the napkin" coughed up this thoughtful form letter printed on equally appropriate material. Talk about handy for a ride home after one too many brainstorms at the pub.
I can't find any info on the brilliant creator, but the lifesaving device can be purchased from a UK gift and gag shop.
Cabbies probably love it too. Especially when it says "look for my cash in my thong." Really.