If you've ever worked with a huge Photoshop file, you know that it's easy to get lost between the dozens of layers. If you have a large pasteboard with several elements, you can get frustrated trying to find the layer that contains the image you want to move/apply filters to/etc. The tiny thumbnails in the layers palette doesn't do much to help, however, there is a way to do it. Hold down the Control and Command (aka Apple) keys, and click on an image in the pasteboard. A menu will pop up, showing the name of the layer it is on. By selecting the menu item, you switch to the layer.
You surely know that in PhotoShop you can drop the foreground color to the swatches palette for later reference just by clicking on an empty area of the swatches palette.
But, did you know that it's as easy to delete one too? Unfortunately just dragging the swatch out won't work. However, you can drag it to the tiny trash icon. Even simpler is to press the Alt (Option) key and the cursor turns into a scissor that will allow you to delete a swatch instantly just by clicking on it.