One of Logitech's better-liked models (4.5/5 stars on Amazon) but curiously absent from the Australian market. This has been my main mouse for the past couple of years and is a good option for people who don't want a HyperScroll wheel (which tends to have inferior click/tilt) but would still like a decent-size, Unifying-compatible mouse with side buttons.
Deal ends in about 12 hours (7 PM AEDT). Price is AUD through Amazon's currency converter; USD option may work out a little cheaper depending on your bank's fees.
M750 trackball is at a low of $27.50USD + shipping as well for those that missed it a few months ago.