Tesco Mobile have the Motorola L7 SLVR in Red for just £89.97 on pay as you go. Port your old number to them and they'll give you £5 free airtime!!
When you buy this phone 10% of any credit you use will be donated to charity to help fight AIDS/HIV in Africa, so it's for a really good cause as well as being a great phone.
The Motorola SLVR L7 Red is one of the thinnest handsets in the world - only 11mm thick. It packs in Bluetooth, a VGA camera with video record, MP3 player, Java games, polyphonic ringtones and a 176x220 pixel display.