James thinks I should get one of these. It is a kind of "everything meter". The idea is that you can just connect an electronic device and it will tell you what kind of device it is. It can detect and measure resistors, capacitors, coils, diodes and a few different types of transistor. For around fourteen pounds I reckon it is a bit of a steal. Very tempting. If you've not already got yourself a multimeter I reckon one of these would be at least as useful.