FOr flying in the mountains of SW England, I normally carry a mobile telephone, and a packet of tobacco with lighter. I'd hate to get stranded somewhere withough being able to spark up
I normally carry enough money to be able to head off to the nearest pub to get hammered to celebrate still being alive as well.
For further afield, I carry all of the above plus an ELT, and one of those shiny survival blankets. For the long journey across the channel, I also carry a liferaft, life jackets, and may wear a dry suit.....
EA