Those cases likely carried Jepp kits, for the entire US.
In my bag I have approach plate books, plus charts, etc. I used to carry a book of LORAN/GPS coordinates, but these are now in my Palm computer. I have my ops manual (required, along with the approach plates & charts), a rain suit, a lumbar cushion, a kneeboard, headset, LED headlight for preflights, flashlight, survival vest, notepads, a small bottle of water, sunglasses, spare batteries, and that's about it.