I remember the cuts that rod222 posted. I think they were from early 1960's postage paid cards. Many collectors turn away from these items, but since they legitimately met a postal use in that day, I find them very collectible.
In fact, here are some of my cuts from the 1940's and 1950's (I saved these primarily because of the postmarks). Never quite understood why the local post offices would have bothered to postmark these sort of corners, except perhaps to document the date of delivery. Anyway, these are especially interesting because every now and then I come upon DPO's (discontinued post offices) which make for interesting cancellations to collect.
