Here is quite a clever remote relay design. I wish they would up it to 15-20amp instead of just 10. I do like it though.
10A DC 6/9/12/24V RF Remote Control Switch---One Transmitter Controls 4 Receivers
In summary, this means you can install 4 different receivers in different location and switch them from one switch.
http://www.rfcontrolsystem.com/index.php?main_page=product_info&cPath=279_416&products_id=1678
10A DC 6/9/12/24V RF Remote Control Switch---One Transmitter Controls 4 Receivers
In summary, this means you can install 4 different receivers in different location and switch them from one switch.
http://www.rfcontrolsystem.com/index.php?main_page=product_info&cPath=279_416&products_id=1678