Windows only: Freeware application iTag edits your photos’ IPTC metadata to add titles, descriptions, and tags to your images.

The cool thing about iTag is that the IPTC standard that it uses is compatible with a lot popular photo applications, both online and off, like Flickr and Picasa. The handy part about using iTag with your photos before you upload them to Flickr, for example, is that the tags you add to your photo will be the same locally as they are on your Flickr account. Aside from that, iTag offers geocoding tools and a simple and quick interface (though a right-click entry would be nice). iTag is a free download, Windows only, requires .NET 3.0.

iTag [via BrentEvans]