It's going to take me a while to add these to my usual workflow. Some I know, the interesting new ones are bold. Read the article for details ...
You’ve probably got the basics of the Application Switcher down pat by now: press Command-Tab to see a bar full of running-application icons and keep Command down as you tap the Tab key to quickly switch to the application of your choice.
2. Open a new window [good for dealing with minimized windows]
... Command-Tab to the program in question and, before you release the Command key, press Option. Release the Command key first, and then the Option key... If the target program’s windows are all minimized, the most recently minimized one returns to duty. If no windows at all are available, a new one is created.
3. Open a document in a different program
When you want to open a document in something other than its default application—a Word file in Pages, say—you can use variations of the Finder’s Open With command. But if the target application is already open (and can handle the document), you can also just drag the file from the Finder onto the Application Switcher bar. The trick is to start the drag operation, and pause it with the mouse button held down, before you press Command-Tab; keep Command down so the bar stays on the screen, and drag the document onto an application’s icon.
4. Bypass the Clipboard
You select a swath of text from a Word document to transfer to a document in InDesign, and realize you can’t Copy and Paste because you’ll lose what’s already on the Clipboard. You can transfer the selection using the Application Switcher instead.
Drag-and-drop a piece of selected text to another application using the Application Switcher.
Start dragging the selection in the Word document (move it a little bit and then stop). With the mouse button still down, press Command-Tab. Holding Command down to keep the Switcher open, drag the selection into the InDesign icon. You’ll be switched to InDesign, where you’ll see the usual “ghost” of a dragged selection, just as if you were dragging it within the InDesign document itself. Drag it into position and let go of the mouse button.
The target window isn’t frontmost in the destination? Hang on to the selection by keeping the mouse button down, and press Command-~ (tilde) to cycle to the correct window. You can also use Command-N to create a new window as a drop target.
5. Hide and show background applications
You’re in Pages. You can see only Finder windows in the background, and you want to refer to a Stickies note. You don’t have move to background applications to rearrange windows or to hide them as you leave. Instead, press Command-Tab to open the Application Switcher, tab to highlight the Finder, and, with Command still down, press H to hide the Finder's windows. When you release the Command key, you’ll still be in Pages.
Unhiding a background application is a little tricky because if you repeat this procedure (in this case, tabbing over to the Finder and pressing H), the background windows will reappear, but you’ll also be switched into that application when you release Command. To make the windows reappear while keeping your Mac’s focus in the current application, you need to press Command-Tab, tab to the application icon, press H to unhide its background windows, and then press Esc while the Command key is still down. Release the Command key and you’ll still be in the original application.
6. Jump to an alphabetical Exposé
You can quickly trigger Exposé when the Application Switcher is on the screen by pressing the Up or Down arrow; you’ll see the windows for whichever application was highlighted in the Switcher bar.
If you know the trick for arranging Exposé windows alphabetically—pressing Command-1, you’ll be pleased to know you can jump right to this alphabetical arrangement from the Application Switcher. Instead of using the Up or Down arrow key to open Exposé, highlight the application you want and press the 1 key (you're already holding down the Command key). Hold it down for a couple of seconds. What’s happening is that Exposé is triggered, and then it notices that Command-1 is being pressed and so offers the alphabetical arrangement—you’ll see the windows swap into correct positions.
I didn't even know the Cmd-1 trick. It's neat! Sheesh.