Photoshop is such an elaborate program that it takes years to figure it all out. Then when you finally think you know everything, they add more features or you discover features that you never knew were there this whole time. This video by Photoshop Product Manager Bryan O'Neil Hughes explores a variation of methods and techniques.
This hour long video is a buffet of random tutorials that has plenty of good information. Granted, you may be someone who knows much of it, you can still find something new. For me, it was expanding on Color Lookup Tables that CS6 and beyond has. Even after all these years, I still discover things that were right under my nose. If you're someone who is still discover Photoshop, this will be something you'll gain a lot out of as well. Anyway you slice it, this has something for everyone.