Some favourite keyboard shortcuts:

• Switch tabs: ⌘-shift-[ and ⌘-shift-] ; Close tab: ⌘-w
• Open Spotlight to search for things: ⌘-space
• Once you’ve found something in Spotlight, use ⌘-click to open its containing folder
• Screen capture ⌘-ctrl-shift-4: allows you to select a rectangle, which will then be available in clipboard (paste straight into email or save by opening Preview and ⌘-n)
• Switch Application: ⌘-tab (hold ⌘ to select)
• Switch Window within application: ⌘-~
• Page up/down/home/end: Fn-up/down/left/right

Command-line tips

• Use open to open an app, or to open a file
• Use pbcopy to dump the output of a command to the clipboard
• Use pbpaste to dump the clipboard to standard output (for piping into a program or a file)
• Drag files into the command-line to get their path (see below)

Some other neat things:

• An icon in the status bar like or can be dragged (yes, even a file you have open in word).
  • Drag it into your Terminal app to get the path to that file.
  • Drag it into your email to attach it.
  • Drag it into your web browser to upload it (in some contexts).
  • This one’s pretty cool: drag it into a Save As or Open dialog (where you get to select a file) to go to the file’s directory!
  • You may want to use ⌘-tab and ⌘-~to navigate to the destination window while dragging.
• The icon next to the URL in your browser – such as the padlock here – can also be dragged, so you can insert the web address in your terminal or email.
• Install ITerm2 and install its shell integration. Among other things it gives you a status bar showing you what processes are running in that shell, the git branch / status, etc.
• Is Time Machine backup taking too long? Open terminal and enter sudo sysctl debug.lowpri\_throttle_enabled=0 to speed up the process.