In the last month I've found
* wallet/checkbook (returned to owner)
* green bandana (kept it but bleached it out just to be sure it was clean)
* screwdriver (it's now in my kitchen drawer, thank you very much)

And about a hundred 1/2" PVC elbows. Actually they were scattered all over the shoulder of the road in a minefield pattern but I left them there.

You never know what treasure you will come across.