app/utility that will assign an screen edge to a key combo

I just downloaded SizeUp for macbook. Basically is gives it an "aerosnap" like functionality, but instead of a screen edge activating it you need to use a key combo. I was wondering if there is an app/utility that will assign an screen edge to a key combo. e.g. left screen = command ->

please help
thanks in advanced

Not sure about that app but if u are on Snow Leopard then this is the screen in System Preferences to add shortcuts for Apps;


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