Well, I'm probably odd in that I'm not interested in things like the grail, Chachopoyan idol, etc., because I want to limit myself to things Indy actually got away with. The exception I've made is the (hematite sphere) "black pearl" from Indiana Jones and the Emperor's tomb.
The cloth was done because it is a key prop from my favorite Indy flick, and it was $6 to make.
The rest are mostly antiques I've aquired. Fun note: though the text can't be read in the pic, the photo of the Indian people is from the thirties and is labeled as being a photo of worshippers in front of a temple of Kali. Can't get much more Temple of Doom-y than that!