This project allows us to use an Arduino to control any AC powered device, including lamps and small heaters. Its limited to 20A, but a lot can be done with 20A. The picture below shows it running two 12V PC case fans. The arduino Uno controlling this device is located underneath the board (out of view in the picture).
A video of this device in operation may be found here:
Datasheet, parts list, and Eagle files for this device can be located here. the GNU General Public License applies to this device and its files. Please let us hear your comments or questions on this device!