This script will apply user-entered text to the "Category" tag of each of the selected tracks. iTunes 5 or better.
(Note: In order to launch this PowerPC-era script on an Intel machine, it must first be opened and then saved using AppleScript Editor, which is located in your /Applications/Utilities/ folder. More information is here.)
Use info from a selected track to search IMDB
Batch merge and/or delete playlists
Set choice of various number tags of selected tracks incrementally
Remove iTunes tracks disassociated from files
Change video kind and video related tags of selected video tracks
Create a playlist for each entry of a specified tag