How to get PCs IP for WakeOnLan over internet (only by using stock Windows 7 applications)
Solution 1:
You will not be able to wake-on-lan from over the internet directly, as wake-on-lan doesn't operate with TCP/IP. You will need a host inside your LAN that can send the appropriate packet.
However, there is no way around using DynDNS or a static IP - that is the only way to contact your network from the rest of the internet; That's like trying to find a building in a foreign country without having its street address! You could always find out the IP while you're at the computer and then memorize it and hope it doesn't change, but that may not always be the case.