Forget print ads. Forget TV, radio, or billboards. Who needs them if you can advertise on trash bins?

Make that Ad Bins, as Keith Clayborne calls the ad-covered receptacles he plans to place outside convenience stores. His start-up isn't alone. More than 100 alternative ad media sprang up during the '80s, says Bob Flood of ad agency DMB&B. Many don't last, but on the whole, nontraditional media are making gains. Ads now appear:

* I n stores. That means messages on aisle directories, in-store videos, carts, refrigerators, bicycle racks outside -- and taped ads mixed with music.

* Wherever groups congregate. There are ads in schools, health clubs, and bowling alleys; on call-in and on-line information services; in malls and inside golf-course holes.

* Near captive audiences. You can't escape ads on telephone hold or on airport scheduling screens. Ditto for ads in restrooms, cinemas, and phone booths, or near theme-park lines.

* Anyplace left. Don't forget ads on ATM receipts, vending machines, taxis, trucks, floppy disks, and video boxes -- as well as on mini indoor blimps or full-size glow-in-the-night models. Then there's the new Talking Poster, which senses passersby and starts a recorded message. What's next? One company is testing slogan-decorated eggs -- and another is planning ads on hot dogs.

-- Martha E. Mangelsdorf