There is something bizarre about your sandwich. For one thing, the bread is homemade. You can tell, because stamped across the top of the crust, in bright purple, is the word HOMEMADE.
You lift off the top crust and see a piece of cheese with a rubber-stamped mouse parading across it. And the bologna below is marked - oh, horrors! - DECEASED.
A rubber stamper has been at it again.
Members of a peculiar elite of children, artists, frustrated postal employees , and others, rubber stampers add facts and whimsy to our day. ''There are so many potential uses,'' says David Hachmeister, editor of Marking Industry Magazine in Chicago. ''Every business uses a rubber stamp.''
Since the first stamp was invented to mark the growth of bureaucracy about the time of the Civil War (the stamp trade is still debating its exact origin), the marking devices have helped to certify meat, date library books, collect overdue payments, and mark eggs.
Which leads us to the ingenious solution proposed by a Wyoming legislator awhile back, who wanted to make sure each egg in his state was properly marked. The esteemed representative suggested that ''each little red hen'' be required to swallow a rubber stamp, which would impress on her eggs information required by the state.
The measure was defeated, but for decades eggs were carefully marked with their grade by the farmer gently tapping them with special stamps - the same sort of stamps used for stamping brand names on golf balls.
Stamping for business was quickly followed by stamping for pleasure, with stampers canceling their checks with ''Thanks!'' signs, marking their presents with impressions of pennies and the words ''Cheap Gift,'' and labeling their household belongings ''A Box of Household Junk,'' ''Another Box of Household Junk,'' and ''More Household Junk.''
There are more mundane uses, of course - stationery stamped with progressively hopping bunnies, wrapping paper covered with smiling Santa Clauses , T-shirts inked with trailing flowers. Then there are the community theater groups who use roller stamps to make instant wallpaper designs; the engineers who use stamps set in clear plastic (the better to see the blueprints with) to mark trees on plans; the embroidery artists who stamp their stitching patterns onto cloth; and the dollhouse collectors who use miniature stamps to make miniature wallpaper.
Finally, there are artistic stamps. Since the 1950s people like Andy Warhol, Saul Steinberg, and Yoko Ono have stamped out books, prints, sculptures, paintings, and multiples. Poet Ray DiPalma combines rubber stamp images of monkeys and toothbrushes, pigs and boats, soap and trains, in his limited-edition ''published paper objects.'' And a woman named Anna Banana stamps her correspondence with a certificate bestowing life membership in THE ROYAL ORDER OF BANANA.
The secret to all this artistic outpouring, according to Joni Miller and Lowry Thompson, authors of ''The Rubber Stamp Album,'' is that stamping ''removes creative blocks. It makes instant art and accompanying instant gratification possible for anybody who can't draw his way out of a paper bag. It is completely possible to look canny and clever without actually being able to do more than give a piece of paper a good swift whack.''
Or you can start with a simple eraser and an Exacto knife and make your own. A teacher in a California college used this in her classes in the 1960s, asking her students to create a complete alphabet from pencil erasers.
Felt stamp pads for inking these creations can be found in any dime store, although purists prefer something called Carter's Micropore Stamp Pads, stocked by the Bizzaro company, for their ability to make a good impression.
Nearly any kind of paper will take to rubber stamping, except erasable typing paper. Generally, the smoother the surface, the better the impression; avoid rough stuff like newsprint. Stampers also advise that you slip a magazine under the paper before stamping.
When you've finished whacking away, they suggest you wipe off your stamp with a cloth and ''gently scrub the surface of the rubber with an old, dry toothbrush.'' Commercial cleaners are not recommended as highly as ordinary denatured alcohol, or nail polish remover.