A nice feature when selecting or manipulating files which compliments the Select all function is the Invert Selection option. If you have never used it, this does exactly what it sounds like: unselects all previously selected files and selects all previously unselected files.

While I don’t use it all that often, I started recently taking advantage while testing some applications which produce log files. I select all the log files in a certain directory and view contents. After running the program again I simply invert the selection and open all the now selected log files. If I find the new log files addressed errors in my old files, I invert the selection again (selecting the previous files), and delete them.

While this situation isn’t something I run into every day (thankfully), it did help me realize how useful this function can be in certain situations.