Ctrl Z is the magic undo combo. It simply undoes your last action, say, the paragraph you accidentally erased (it works in other applications, too).

Programs vary in the number of times you can undo something, but some will let you Ctrl Z all the way back to the beginning. (And, yes, there is a redo command, just hit Ctrl Y.)

Ctrl B, Ctrl I, or Ctrl U apply bold, italics, or underline to highlighted text, respectively.

Ctrl P prints whatever is in an active window.

Ctrl Backspace erases an entire word at a time, instead of a letter.

Ctrl up or down arrows let you scroll an entire paragraph at a time, instead of one line, and Ctrl Shift up or down arrow will select an entire paragraph.

Ctrl Enter inserts a page break in Word.

Alt Ctrl C inserts the copyright symbol (Alt Ctrl R inserts the registered trademark symbol, and Alt Ctrl T makes the trademark symbol).

In Outlook, you can jump to the section you want: Ctrl 1 switches to the Mail window, Ctrl 2 switches to the Calender, Ctrl 3 to Contacts, Ctrl 4 to Tasks, and Ctrl 5 to Notes.

Ctrl Shift M starts a new message in Outlook. (Use Ctrl Shift C for a new contact.)

In Outlook e-mail, hit Ctrl N to compose a new message, Ctrl R to reply to a message.

In Microsoft Excel, you can select the entire column by pressing CTRL SPACEBAR, and select the entire row with SHIFT SPACEBAR.