From Power of Two Software:
One of the finest WOL apps on iTunes - wake your Mac or PC remotely with the touch of a finger. NetAwake uses Wake-on-LAN technology that allows you to wake up computers from your iDevice. The integrated Bonjour browser automatically finds eligible machines, so you don't have to waste tens of seconds typing long, unwieldy MAC addresses! NetAwake is iAd supported. Note: Wake-on-LAN only works with computers plugged in via ethernet, or over Wi-Fi for some newer machines.