Tax stamps were released by the United States as receipts for taxes and fees paid. Classified as "revenue" stamps, as opposed to postage stamps, they are part of what collectors call "back of the book" stamps. Many types of revenues can be found inexpensively, as they are more oddities than highly sought-after rarities.
Playing Card Tax Stamps
Most playing card tax stamps were affixed over the lip of the box of playing cards. The special tax on playing cards extended from the Civil War through 1965.
Tobacco Sales and Cigarette Tube Stamps
Before there were packs of cigarettes, people would roll their own cigarettes or insert tobacco into cigarette tubes; both the tobacco and the tubes were taxed.
Wine and Beer Tax Stamps
Between 1866 and 1951, stamps to pay taxes on alcohol were affixed to kegs and barrels of beer and fermented malt liquor as well as cases of wine and other spirits.
Silver Tax Stamps
Purchasing silver tax stamps paid the taxes on gains from the sale of silver bullion and were attached to the transfer memo. The stamps were used from 1934 until 1963.
Many revenue stamps were issued by local state governments to collect their taxes as well; though not official U.S.-government issued revenues, they're still collectible.