<Ctrl><Alt><F1>
Switch to the first text terminals. Under Linux you can have several (6 in standard setup) terminals opened at the same time.

<Ctrl><Alt><Fn> (n=1..6)
Switch to the nth text terminal. (The same could be accomplished with the rarely used command chvt n.

tty
Print the name of the terminal in which you are typing this command.

<Ctrl><Alt><F7>
Switch to the first GUI terminal (if X-windows is running on the 7th terminal, where it typcially is).

<Ctrl><Alt><Fn> (n=7..12)
Switch to the nth GUI terminal (if a GUI terminal is running on screen n-1).

<Tab>
(In a text or X terminal) Autocomplete the command if there is only one option, or else show all the available options.

<ArrowUp>
(In a text or X terminal) Scroll and edit the command history.

<Shift><PgUp>
Scroll terminal output up. This works also at the login prompt, so you can scroll through your bootup messages.

<Ctrl><Alt><+>
(in X-windows) Change to the next X-server resolution (if you set up the X-server to more than one resolution).

<Ctrl><Alt><->
(in X-windows) Change to the previous X-server resolution.

<Ctrl><Alt><Esc>
(in X-windows, KDE) Kill the window I am going to click with my mouse pointer (the pointer changes to something like a death symbol).

<Ctrl><Alt><BkSpc>
(in X-windows) Kill the current X-windows server.

<Ctrl><Alt><Del>
(in text terminal) Shut down the system and reboot.

full list: csdn.net

1. Tab

The most handy shortcut and time saver for the linux command line.

2. Ctrl + c

Stop that program dead in its tracks.

3. Ctrl + z

Send the current process to background.

4. Ctrl + d

Log out from the current terminal.

5. Ctrl + u

Erase the current line.

6. Ctrl + Alt + F1, (F1-F6)

Switch to the first virtual terminal.

7. Ctrl + l (lowercase L)

Clear the terminal.

8. Ctrl + Alt + Backspace

Kill the X server.

9. Ctrl + a

Move the cursor to the beginning of the current line.

10. Ctrl + e

Last but not least get that cursor back to the end of the line.

via marksanborn

1: Ctl + Alt + Backspace

Use this shortcut when X isn’t responding or a program has locked up your desktop and you can’t get anything to respond.

2: Ctrl + Alt + Delete

This is the big kahuna.

3: Alt + Tab

This handy shortcut allows you to cycle through all open windows, stopping on the window you want to have focus.

4: Ctrl + Alt + F*

This is one of those mack-daddy shortcuts you very well might need to use.

5: Alt + Arrow key

If you’re using Linux, you probably know about the pager that allows you to have multiple desktops at one time.

The following apply only to terminal (aka console) windows

6: Ctrl + a and Ctrl + e

If you are working in a text editor like Nano (from within a terminal window), you can get to the beginning of a line with Ctrl + a and the end of a line with Ctrl + e.

7: Ctrl + c

When you have a process running in a terminal window (say you’re following a process with the tail + f command), you can kill that process with the Ctrl + c combination.

8: Ctrl + z

This will zombie an application. If you have a process running in a terminal and you want the terminal back but don’t want to kill the application, you can hit Ctrl + z to send the process to the background.

9: Arrow up or Arrow down

The up or down arrow key, when in a terminal window, cycles through the history of commands you have issued in the terminal window.

10: Ctrl + r

via 10 Things from Tech Republic