Small timer for the fireworks I left under the table. Just a little startling, never to harm, of course. Wouldn't be good to harm a slimy salesman, then he wouldn't learn his lesson. Was considering something stronger, but you're right, I think this is best way about it. It's just like the tale of Sisyphus and his giant boulder. He pushed and pushed that boulder until he learned to build a proper lever... and explode it by pulling that lever, clearly attached to a thermonuclear detonator!

[ HOW IS HE SO NONCHALANT. ]