Update Something had been bothering me as I've interacted in this thread. It's the "why can I wake my Macs on my home network and these guys can't w/o the WOL app?"
So, using Google Mac (searches only Mac related sites), I found a very interesting article on
MacWorld's site. My home network uses an Apple Time Capsule as the wireless router. As the article points out, recent Apple Base Stations and Snow Leopard work together, using Bonjour, to allow recent Macs to wake on network access. That's why I remember that my Macs wake up with Screen Sharing. (I also have the Mac's Sharing Preference options for Remote Login & Remote Management enabled.)
Now, I (think) know why I can wake up sleeping Macs. But I have to solve why my Hackintosh can't be waked up from sleep. I now think it might be the Ethernet driver.
Hope this helps.