Genghis the emergency loo roll is inspired.
Depends where you fly I guess. I've always got loo roll in my backpack, because I've several times visited places where it turns out to be necessary, but the loos at most of the local burger run joints are better than that
My bag (which is a standard floppy briefcase-type thing without any mark-up due to being called a "flight case") contains
- pens, pencils, rubber etc
- clipboard, PLOG for the flight, pieces of paper with useful magic numbers (performance, W&B etc) for the club aircraft
- nav instruments (ruler, protractor, whizz wheel, gadget for plotting position from VOR/DME fix on IMC tests) (none of which, apart from the last during IMC tests, are used in the aircraft)
- half mil chart, local & diversion approach plates, whatever seems like a good idea printed off from the destination airfield's web site
- Pooleys
- spare glasses
and that's about it apart from
- a bunch of other stuff I've forgotten about and never use
which obviously you don't need.