Travel mice: mostly a bit rubbish. If they're not RSI-inducingly small, they track poorly, or have pants battery life. Consider this fellow the very saviour of the sector, then.
Some really intelligent design has gone into the Ci75M; the wireless dongle packs away flush into the underside, turning the unit off at the same time.
And if it the two AAA batteries run out (Duracell included!), you can pop the top off, unspool the hidden mini-USB cable, plug it into the back of the wireless receiver, and use it wired. It's sleek and low, but comfortable due to its large surface area.
In short, it's pretty much perfect all round, and even looks swanky. Hats off.