WakeOnLan discovers all other computers in your LAN, and enables you to wake them up by clicking a button. If your remote computer is a Mac you can put it asleep too.
Scheduled Wake Up Calls
In addition to timer based wake up calls, each computer can be scheduled to be woken up frequently at a day of the week (or, weekdays or weekends only) and time of your choice. For example, schedule wake up calls each Sunday night at 04:00AM for backup.
WakeOnLan Dashboard Widget
You need to wakeup some other computer quickly, but don't want to start the WakeOnLan application? Just press F12 and use the WakeOnLan Widget. Simply select the computer to be woken up and click on the sun. Press F12 again and you're done.
New for all Mac OS X versions: Dock Menu
Faster access for everyone. Click and hold the WakeOnLan icon in the Dock (while WakeOnLan running), and select any computer to be woken up or put asleep directly from the menu. It doesn't get any simpler.