Halfords have this Navigon 1200 Satellite Navigation system reduced from £139.99 to £59.99. Delivery is free, or you can buy online and collect instore if you're nearby.
Navigon 1200 UK & Ireland Sat Nav is an entry level satnav device powered by a 375Mhz processor and a 64MB RAM, with a 3.5-inch screen for displaying the maps.
* 3.5" touch screen display
* Full postcode search
* Pre-loaded UK & Ireland street level mapping
* Pre-loaded safety camera data*
* Lane guidance with Lane Assistant Pro
* Reality View exit signposts
* Speed limit indicator
* 2M points of interest