Power consumption is important factor on battery driven devices. We all want them to last longer. In order to build energy efficient projects testing is necessary step. Small changes in circuit or in microcontroller software may lead to different current drain.
MechG has built a handy power meter dedicated for breadboard tests. It is based on MSP430G2402 microcontroller which samples voltage and current consumption of target circuit and then calculates power usage. Data is displayed on LCD. It is capable of measuring voltages from 0 to 10V and currents from 0 to 300mA. Measuring resolution is different for uA and mA ranges that are 0.1mA and 0.1uA respectively. Full specs can be found on Google code page. I think this is a “must have“ tool for any circuit you design – even if it’s not battery operated.