Belkin N150 Wireless Cable Router (Wireless N - Up to 150Mbps), £10.69 delivered @ Amazon UK. Suitable for Virgin/NTL/Telewest connections.
Quick tech details:
4 Ethernet Ports for Wired Connections
Supports Wi-Fi Protected Setup Push button for simple wireless security setup
Easy setup Assistant and troubleshooting with Network Status Display which shows the status of your network
Free 24/7 technical Support (Local Rates Apply)
Manufacturer's Lifetime Warranty
Suitable for CABLE connections: Virgin/NTL/Telewest
Speed of up to 150 Mbps and a range of up to 300 meters
Cheapest I've personally found online. Just ordered one myself to replace our dated Belkin Wireless G Router which is still going strong. Comes with a Belkin lifetime warranty unlike other manufacturers. Good for someone who's looking for a low - mid range wirless N router.