£25 for a basic phone that will survive some pretty harsh treatment.
Builder mates of mine have these phones because they last. Spec wise they aren't great, but if you only need to talk and text they are reliable. This is also an excellent glove box phone because it'll happily work in extremes of temperature (most smartphones throw a strop if they get too hot or cold in a car).
It's 2G only, so won't work on the Three network, and you can forget about internet access, but it does have Bluetooth for those important calls when on the move.
The rugged JCB Tradesman 2 - SIM Free
If you're looking for something a little studier than your average handset the JCB Tradesman 2 is as tough as they get.
Built to Military Specifications the Tradesman 2 is water resistant, certified to IP67, dust resistant and has a special plastic casing which has been hardened.
Despite it's tough design, the Tradesman 2 comes with a great battery with 350 hours of standby time and 300 minutes of talktime. It also has a camera with auto flash.
The Tradesman 2 has built in FM radio and a MP3 player and even operates in temperatures from -20ªC to 55ªC, it's a perfect handset for construction and engineer workers.