ZapsTick

I actually searched for things like that after posting.

It's already a thing*, in many different variations. Some use piezo-electrics, advertised as 'battery free'. And countless other stuff, many with some variation of Zap(p) in their names.

*Sort of, didn't see small 'passive' ones powered by USB.

Edit: Thinking about it, one could abuse and modify one of the countless e-vapes for it? Small enough in most cases, and self-powered.