In an older version of WinRAR there was a bug where you could extract the file, but it doesn't complete until you give the password (or something along those lines). At that point you'd have to find the file in the temp folder or where it was extracted to, and make a copy of it to another location. I doubt it still works though.
Sorry, but you can't crack it. Their is software out there for passwords, but all they do is guess the password. Basically they use a dictionary and try every word. They really don't work for a complex password.