A compact but powerful, PICAXE-18M2+ microcontroller. Very popular in education due to its low cost and small size, but also very popular in a wide range of hobbyist projects.
This chip supports up to 16 inputs/outputs with 10 analogue/touch sensor channels.  
All M2 series parts support enhanced features such as configurable i/o pins, parallel tasks, ring tone music and touch sensor inputs.