O2 stores in the UK are selling the Harmon Kardon Onyz Studio Portable Wireless Speaker for half price at £99. This started life as a $400 speaker.

More info here Harmon Kardon

This is a bad boy of a speaker. Bluetooth. Powered by mains or battery which lasts 5 hours.

To get this deal you need to be with O2 Priority Moments. Next open the O2 Priority Moments app on your smartphone and the speaker should appear. Get the code. Then head off to your local store.