1) Download AutoHotKey from
www.autohotkey.com
2) Save the script as a .ahk file (make sure it is .ahk and not .ahk.txt, if necessary go into folder options under tools, and in advanced uncheck 'hide file extensions for known types, then rename it)
3) Double click the .ahk or if you want, use ahk2exe that comes with AutoHotKey, to build it into an exe that will sit in your taskbar
That should be it.. Enjoy!