The people at a company called aiia (their Web site loads insanely slowly) out of the Ukraine pitched me the SSSSSpeaker (yes, that's how they spell it, it's not a a typo), billed as the world's smallest Bluetooth speaker, and sent me a unit.
It is, I grant you, a little odd-looking but it's pretty small and its collapsing silicone shroud (no, it does not double as a cup) makes it even smaller (it can fit into a space 3.25" by 3.25" by 1.75"; that's about the size of an unusually thick hockey puck).
The sound? Surprisingly good for such an odd format; the bass is weak, the mid-tones OK, and the treble a little bright but, as I wrote, surprisingly good.
It's rechargeable and has a reputed 8 hours of play time.
The price? $19 for a wired version and $26 for the Bluetooth version. Cheap and cheerful. What's the tag for on the edge of the speaker? No idea.
Want to get one? Their Kickstarter campaign has, as of writing, just 13 hours to go closing at 08:27AM PDT on Friday, August 8, 2014 ... it's really close to funding!
Here's their promo video; it has got a kind of annoying soundtrack but, whatever ...