Known as the “first talking stamps” in 1972, these tiny vinyl postage stamps from Bhutan were totally playable and when the needle was put on the record stamp you heard Bhutan’s national anthem and a capsule history of the nation. Talking stamps were thin plastic embossed records with removable back to expose the adhesive.
According to eBay, they’re highly collectable (an entire set is around $495.00) and even still legal for mailing use.
WFMUhas a few samples of what these tiny vinyl stamps sound like. You can listen to them here.