Control+F6 toggles between multiple Word or Excel files when you have more than one open, or between worksheets when you have more than one Excel file open.
F7 opens the Spell Check dialog box in Excel, Word, and Outlook.
Shift-F3 Change Case toggles the case of the selected text in Word and Outlook, rotating from sentence case to uppercase to lowercase and so on. Just highlight the text you want to format and continue to press Shift-F3 until the case you want appears
F4 Repeat last action you performed in Word. For example, create a text box, insert a graphic, or draw a line, then press F4 and the action is duplicated.
Shift-F7 Opens the Thesaurus dialog and gives suggested synonyms for the selected word.
F11 in Excel creates a chart of the data in the active range of the active worksheet. Tip: highlight the range first could save time when editing the chart.