Often times, when working in Photoshop, I will use the trial and error method of adjusting images. With the preview button checked, I can see the immediate effect of the adjustment, and will sometimes find it not to my liking (this happens more often than not).
In the past I would cancel the adjustment only to have to re-open the same adjustment window to make another attempt. Well, NO MORE!
By holding down the Alt/Option key my cancel button magically turns itself into a reset button...this has become an invaluable time saver for me.
If you find this post helpful, please leave me a comment. Thanks!