In the 1960's, Al O'Hagen invented an absolutely killer close-up bottle suspension / levitation, which he called Al-Levito. At some point, (I think in the 1990's, but just guessing...) Jay Leslie purchased the rights to keep making and selling this amazing little gimmick. My recent check of Jay Leslie's website did not show the item for sale any longer. But if you want to own and perform this neat close-up miracle, you can still get one right here.
The effect is simple: an empty beer or soda bottle is stood on the table, mouth up, and a matchbook is placed on top of the bottle mouth. The book of matches is lifted and the bottle clings to the matchbook, levitating under the matchbook.
The bottle and matchbook are ordinary, and can be borrowed. The secret (and ingeniously simple) gimmick is almost invisible, so you end super clean, and you can get ready for this one, practically in plain sight. The effect is technically not impromptu, but if you carry the gimmick in your wallet at the ready, it will look impromptu to your audience.
Can't show you the gimmick in the photo of course, but the effect looks just like the illustration of the floating bottle beneath the matchbook.
This is from Jay Leslie's re-issue of the trick, which featured photocopies of the original vintage instructions and envelope label (as shown in the photo)
Brand new and unused, with instructions.