One the things I've always felt Windows had the edge over OS X with is working with multiple windows at once. Having the taskbar in Windows clearly lets you see how many windows you have open and allows you to easily switch between them. Obviously one of the things this makes easier is moving files between two directories quickly.

They're a few things in OS X to compensate for this; showing small versions of all the windows on screen at once with the press of a button and choosing which to focus on (or assigning this action to a hot corner), spring loaded folders etc, but nothing that makes moving files as easy in Windows in my opinion.

This application opens two finder windows side by side (or one on top of the other), or if a finder window is already open another window next to it. Sounds simple, but when moving files around it definitely has saved me time since I tried it.

One thing I'd like to see would be the ability to customise the finder window sizes (i.e. if no windows are already open they both open at the specified size, if one is already open it is resized to the specified size). If this isn't possible, just not having the extend underneath the dock would would be an improvement.

It would also be nice if it didn't change the size of other finder windows, say when you open the Mac HD disk icon on the desktop mine is now at the size of the pwrwndws windows, but I have a suspicion this is due to the strange way Leopard seems to remember finder view settings.