Well I have just discovered this program and although I like the idea behind it I'm finding it a bit clumsy to use. It seems to suffer from a fatal flaw -
I'm on Windows 7 32bit. If the stack contains enough items that it reaches from the bottom of the screen to the top, then the last few items at the bottom disappear behind the taskbar (superbar). So I cannot select the bottom few items. Making it impossible for me to use. I can't believe nobody has noticed this problem. As long as there aren't too many items, it seems to place itself above the taskbar. But like I said, too many items and suddenly the list drops below and behind the taskbar.
And since Windows 7 took away the ability to choose if you want the taskbar to be "always on top", there is no way for me to bring the stack forward. So I can't use this because of this issue. Shame that it appears to be abandoned.
I also had it stop working like somebody above has mentioned. All of a sudden, it wouldn't work any more, and I had to restart my computer before it would work again. If you open a stack you can see it in the task manager running, but the stack never appears. If you try to open the stack multiple times, you see it multiple times in the task manager. But no stack appears. Even if you end all the processes, and try again, it still doesn't work. For these reasons, I cannot rely on this at the moment. If these important issues can get resolved, I'd happily check it out again. While there are probably some more nice options that could be added, I think the ones I mentioned are extremely important. Eye candy is nice, but not much good if it crashes or has deal-breaking bugs.