I had a bunch of boiled eggs saved in a tupperware, and i was getting ready to record cracking and peeling some, so i decided i may's well record a little rattle too.
Running a corkscrew several times rapidly along the edge of a wooden desk. Recorded with minidisc and condenser mic, indoors, 6" distance. Background noise removed with audacity. Short, rattly hard noises.
A metal tray with teacups rattling slightly and being put down 4 or 5 times. Neutral indoor atoms. Recorded on a zoom h1. Easy to edit to choose the one you like best. Example of it in use can be found at releasetheclowns. Podbean. Com in episode 47.