CMoy-type headphone amps are supposed to be small, right? How about this one, 5.5cm x 3.5cm, small enough to fit in even the smallest Altoids tin! There's nothing tiny about the sound though:
Components included in this kit:

1x NE5532 DIP8 IC.
1x DIP8 IC socket.
2x 220uF electrolytic capacitor.
2x 100nF ceramic capacitor.
2x 47Ω resistor.
2x 1kΩ resistor.
2x 100kΩ resistor.
2x 4.7kΩ resistor.
3x 10kΩ resistor.
1x 5mm red LED.
14x 2.54mm pin headers.

Get into the CMoy vibe for only 9.99 GBP!

PLEASE NOTE THIS IS A KIT OF PARTS THAT YOU WILL NEED TO SOLDER TOGETHER YOURSELF!