I had a cheap Nokia 108 from Tesco, and have just bought a Samsung S5611 on Three (I didn't like the fact that the Nokia showed the content of any text messages received even when the phone was locked and needed a specific charger), the Samsung cost about £40 including the £10 top up. It has a 5mp camera, so not sure if that's good enough? You can also secure a lot of the menu's (text messages, pictures etc) with an additional password to be ultra safe!