We have had a wireless mouse for ages now and love it but it was starting to play up (Scroll wheel was getting jumpy). so decided to get a new one and also went for a wireless keyboard too.
Looked up reviews and found a good set for £19 delivered on ebay.
If anyone is thinking about going wireless I recommend this one: Belkin Wireless Slim Keyboard And Optical Mouse ( http://cgi.ebay.co.uk/Belkin-Wireles...kparms=65%3A12 )
Just plugged in via usb for the receiver and it worked straight away.