Firstly I would recommend building the ether-wake binary from source to ensure that you know what you are using.
If you use ether-wake.gz that I compiled you need to decompress the file.
# gzip -d ether-wake.gz
This will give you the binary called ether-wake
You can read how to use it here:
http://www.scyld.com/expert/wake-on-lan.htmlBasically, if you have another machine on your LAN for which you know the MAC address, eg AA:BB:CC:DD:EE:FF then you can wake it up.
# ether-wake AA:BB:CC:DD:EE:FF
This presumes that you have set that machine for WOL Wakeup-On-LAN, often you need to connect a cabel between your NIC and the Mainboard.
I run this as a cron job to wake up my other PC for overnight backups and virus scanning.