Wake On LAN Ex 2 - Free software from Joseph (AKA BootBlock) of http://www.bootblock.co.uk
Advanced Port Scanner - Advanced Port Scanner is a fast and free software for port scanning.
WOL Magic Packet Sender - A free magic packet sender for Windows - wake-up computers with the touch of a button.
gWakeOnLan - gWakeOnLan is a GTK+ utility to awake turned off computers through the Wake on LAN feature.
Wake on LAN Tool - Waking up, restarting and shutting down multiple computers made easy.
Nmap - Nmap Free Security Scanner, Port Scanner, & Network Exploration Tool. Download open source software for Linux, Windows, UNIX, FreeBSD, etc.