25 Very Useful Keyboard Shortcuts

 1.To format any selected object, press ctrl+1
2. To insert current date, press ctrl+;
3. To insert current time, press ctrl+shift+;
4. To repeat last action, press F4
5. To edit a cell comment, press shift + F2
6. To autosum selected cells, press alt + =
7. To see the suggest drop-down in a cell, press alt + down arrow
8. To enter multiple lines in a cell, press alt+enter
9. To insert a new sheet, press shift + F11
10. To edit active cell, press F2 (places cursor in the end)
11. To hide current row, press ctrl+9
12. To hide current column, press ctrl+0
13. To unhide rows in selected range, press ctrl+shift+9
14. To unhide columns in selected range, press ctrl+shift+0
15. To recalculate formulas, press F9
16. To select data in current region, press ctrl+shift+8
17. To see formulas in the worksheet, press ctrl+shift+` (ctrl+~)
18. While editing formulas to change the reference type from absolute to relative vice versa, press F4
19. To format a number as currency, press ctrl+shift+4 (ctrl+$)
20. To apply outline border around selected cells, press ctrl+shift+7
21. To open the macros dialog box, press alt+F8
22. To copy value from above cell, press ctrl+’
23. To format current cell with comma formats, press ctrl+shift+1
24. To go to the next worksheet, press ctrl+shift+pg down
25. To go to the previous worksheet, press ctrl+shift+pg up
Courtesy: http://sapost.blogspot.in/