XWOL is a free osax for Mac OS X (10.4 and better) allowing you to wake a computer on your local Ethernet network if it is supporting the magic network packets to wake a computer.
To wake a sleeping computer you must first retrieve its mac address and then execute the following script :
set macAddress to "00:11:24:70:f7:56"
wake on lan macAddressHappy Scripting & Awaking !