When working with white or light grey objects the default checkered pattern that stands for the transparent background makes it quite difficult to see the edges of your elements. It's especially difficult to judge semitransparent areas. I've seen designers adding another locked layer below the working layers filled with a dark color. This is a good solution, except that it adds to the file size and needs to be switched on and off when saving your work with the transparent background as a gif or png.
Dust & Scratches filter is for cleaning the imperfections in your image that are usually a result of of film development and scanning. You may ask, what's to write about this filter? You just select it from Filter/ Noise and done.
PhotoShop CS has an excellent file browser built into the application. You can access it from the File menu or by pressing Apple(Cmd)-Shift-O. It can do all a regular functions Finder does and much more. Many don't realize that you can actually delete/rename and move images, create/delete folders, etc. in this mini application with the benefit of having really big preview icons for your images to help your navigation.
But don't you miss the old times, when you could mark the transparencies on your lightbox and easily arrange them for a selection?
Most of the time when I'm trying to find a specific desired effect I would go through several layer blending modes. This can mean a lot of clicking if done from the tiny drop down menu. I would have to focus to the menu to remember where I was.
Radial blur is a great tool in PhotoShop to dramatize speed, but what if your subject matter is not in the center of your image? If you apply the radial blur filter the speed lines will be incorrect (left image).
I'm not sure how useful you may find this Adobe Acrobat bit, but I've had a reason to use it recently and thought I would share it.
Say you have a large multi-page PDF document stored on your Web site. And lets say you want to link to a specific page in that PDF file right from your Web page. You could split the specific page out of the file, or you could force your reader to scroll to a specific page, but this is a more elegant solution.