Just came across this ad. Sounds like a good deal to me although I personally have never heard of it before.
Description from their website (http://www.promixx.nz/)
What is PROMiXX?
PROMiXX is a world first, completely portable vortex mixer- featuring a battery-powered motor. The powerful vortex quickly blends liquids and powders to achieve smooth, lump-free shakes. You can even taste the difference!
Now blending protein shakes (or baby formula or even cocktails) while on the go is effortless and totally mess free- thanks to the clever leak proof design.
Purchase 2 or more items and use the code Black Friday to receive a further 10% off.
Pretty good reviews on Amazon