TagBot is a metadata tagging program for Mac OS X 10.4
Tag your files by right-clicking them in the Finder...
Find all files with a given tag by double-clicking the tag...
...or by dragging them onto TagBot's tag palette.
...or find them using Spotlight.
Tag your photos with names and locations.
Track invoices and other work documents with status tags.
Organize your AddressBook entries.
Categorize graphics, sounds, and other media files with descriptive attributes.