Ok so this deal was posted before but that was a long time ago and the offers back on, RRP is £14.99 and its sold for more than that at most places, if you can find it in stock.
Id recommend one of these if you game on both Xbox and PC when first release support and drivers were buggy at best but now with the 1.1.2 drivers it works fine and dandy and under Windows 7 x64 as im using it its perfect, most new games come with the Controller premapped like it would be on 360 and its a must for racing games at least!
so as such i bring the offer to your attention again, and credit to the original poster who found this offer first time.
Use Xbox 360 wireless accessories on your PC
30 ft range
Plug and play
Negates need for separate PC gaming accessories, all wireless 360 products are compatible.
6 ft long USB cable