Find revisions that have not been merged in Subversion (requires version 1.5 or later).

This script is useful if you have development happening simultaneously in multiple branches and have a hard time keeping track of what has and hasn't been merged.

Instructions:

cd to base directory of branch or trunk
sh /path/to/show_missing_revs.sh -b (branch that you are merging into the current directory) -u (optional - username) -v (optional - verbose mode)

The script will output something like:
r9943 | bowser | unleashing koopa troopas
r10123 | mario | trying to save the princess
r10127 | luigi | looking cool wearing green
r10128 | luigi | eating mushrooms

This means those revisions are present in the branch specified by -b but not in the current branch.