A few of my favorite keyboard commands:
Ctrl+B: show "flat view" of subfolders. Simple, but you don't want to miss it.
Alt+Shift+Enter: display size of all directories in the current listing. Or press
Space on a folder to show size for just that folder.
Lots and lots of intuitive keyboard assignments. It's easy to see the big
F8 Delete button at the bottom, but you can delete also by pressing Del.
Backspace navigates to parent folder.
Insert selects. Insert is a non-repeating key, so Shift+up/down arrows works just as well, or just press
Ctrl+A to select all. But by far the quickest way to select all files, if none are currently selected, is the NumPad asterisk ("invert selection").
Shift+F1 to quickly change the view or custom column layout, without going through the main menu.
Shift+F4 to create a new empty file and open it in the editor assigned to the F4 key in TC.
F2 (or Shift+F6) to rename current file. If multiple files are selected, you get a dialog box where you can e.g. quickly change the extension of all selected files.
F5 of course copies a file to the opposite pane, but
Shift+F5 does an "in place" copy (in the same folder, not to the other pane).
Tip: Learn the keyboard shortcuts for changing sort order: Ctrl+F4 sorts by file extension, Ctrl+F5 sorts by file size, etc. It's much quicker than clicking the columns.
Tip: If you have added your own commands to the Start menu (the TC Start menu, which predates the Windows Start button by 10 years or so
assign keyboard shortcuts to the "cm_UserMenuX" commands to activate the respective Start menu items. For example, cm_UserMenu1 activates the topmost command in the Start menu, cm_UserMenu2 activates the second command from the top, etc. I use this to quickly open files using different editors: Ctrl+1 opens the selected file in EmEditor, Ctr+2 opens it in EditPad Pro, Ctrl+3 in HippoEdit, and so on.
Ctrl+D opens a context menu that you can fill with custom commands. It's very fast, so I use it to switch quickly to folders I often use. Use the ampersand character to mark hotkeys in the menu, so that you can press Ctrl+D, M for example, to navigate to "My Documents", etc. I probably use it a hundred times a day. You can place any commands you want in that menu (Ctrl+D, select "Configure"), but this menu is specifically designed for folder switching: press Ctrl+D, then click "Add current dir".
Use the lister (F3). It's the simplest but the most efficient file viewer I've
ever seen. With plugins, it can display formatted content of many types of files (there's even a plugin for .torrent files), but by itself it just displays the raw file contents. I couldn't live without it. If you just need to read a file, it's the fastest and most convenient way. Hard to believe, but when you install a fresh copy of Windows, there is no file viewer available at all. You can open text files in Notepad, but if you'd like to see what an .exe file really looks like inside, you're out of luck. The TC lister is fast, has great search with regexp support, and understands Unicode. Check the Options menu to configure the viewer, and press keys 1 through 7 to cycle between various formats and encodings.
Install IrfanView (even if you don't normally use it), and in the lister's configuration check "Use IrfanView to load graphics". This, again, is the fastest way to view any media format that IrfanView supports (including videos and sounds).
Select a file and press Ctrl+Q for quick view in the opposite pane. (But install IrfanView first.) Isn't it simpler than waiting for ACDSee to open and navigating the crowded interface?
Select a
zip file and press Ctrl+Q. If the zip contains a file named "readme" (or a few other common names), it will be displayed without you having to open the zip file and navigating inside it.
Plugins are usually distributed as zip files, too. Press Enter on a plugin file, and TC will ask if you want to install the plugin. (Only the first time though, once per session.)
Tip: A lot of zip files (and other archive files) use non-standard extensions. Pressing Enter will open the file in associated application - but what if you just want to look inside the archive? Press
Ctrl+Page Down. Do it for example on a .docx file (created in Word 2007), or on a .jar file in Firefox's "Chrome" folder, for example. It also works with some (not all) installers, and with all executable archives. Very useful if you suspect an executable might be a trojan, but then again it might be a harmless zip file - instead of hitting Enter to run the executable, press Ctrl+PageDown and just view what's inside. Experiment with it often, and you'll find all manner of interesting files inside files. (Now try doing that in Windows Explorer!)
Tip: Remember that you can save searches that you frequenrly perform (The Load/Save tab in the Find Files dialog box.) And when you search for files, remember that you can press Alt+L ("Feed to listbox") to show search results in one of the two panes in TC. You can also use the file viewer (F3) directly from the list of results in the Find Files dialog.
Want to find files with more than one extension? Separate extensions with spaces: *.doc *.txt.
Remember also that you can search for files (and for text in files) inside any archive format TC understands.
And that's the basic fun stuff