This coffee mug helps you keep your coffee hot, just like a regular insulated mug. But it also cools down your next sip to a “Perfect Zone of 150-170″ degrees. You have to “tip and swish gently” to load the upper chamber and start the cooling process.
This is all done with “thermodynamic transfer technology”, which sounds like they just didn’t insulate the top chamber as well as the bottom one. The “swish” part of loading the chamber probably helps too.

Sounds gimmicky, but if you have tried this, let me know if it actually works.

Product Page, Via Gizmodo