I found an excel add-in within minutes of searching for it online that cracks an excel spreadsheet password and after playing with it for awhile the longest time I can get for it to crack a password is just over 3 minutes. Which doesn't make me feel to good about using this method to protect my data as it is very easy to get around. Is there another way without messing with file security itself outside of excel that would make it harder to unprotect?

I guess what I'm really asking is there a way to lock cells or something without using the built in method that is painfully easy to circumvent.