Scrubby Slider Shift-Click Trick
Adobe borrowed scrubby sliders, a very cool feature from Adobe After Effects, and put it in Photoshop. You use it by clicking on a field's name, rather than in the field itself, and the value in the field changes as you drag (scrub) over the field's name. However, it scrubs in very small increments. That is, unless you hold the Shift key, which is ideal when you need to make big changes in the field (like from 0 to 256).