I have to add a comment on my favorite Ctrl+[ shortcut.
If you are like me and work with spreadsheets that are linked to other spreadsheets and those are linked, etc. and all are buried in several levels of folders, then this is a real time saver.
To to look at those linked files I used to Ctrl+O and navigate over several folders to find one of the spreadsheets I needed. This task was repeated for each of our business sectors and took mucho time. I actually dreaded wading through all those folders just to refresh my memory, or double check a source. That's not the worst of it. Then once I found the source spreadsheet and opened it, I had to return to the original formula to see what sheet within the linked workbook was referenced and then what cell(s) were being referenced. These spreadsheets I'm linked to are massive and that alone took what seemed to be forever.
The beauty with this two stroke short cut is it does all that wading for me and almost instantly finds the workbook and opens to the sheet and cells referenced. Brill!