iTag is a freeware application that simplifies adding titles, description and tags to your photos. The meta data you enter is embedded in to image files using industry standard IPTC headers. Popular applications like Flickr, Picasa, Irfanview, Smugmug, and many others can read this meta data.
iTag provides a simple interface to tag all your photo collection and organize them in tag clouds. Using the search feature of iTag you can search for photos using tags, rating, filename. It also offers Geocoding of photos using GPS coordinates from Google Earth. You can search photos with street addresses after Geocoding your photo collection. If you have Cooliris (formerly Piclens) installed you can generate cool slideshows with your photo collection.
Apart from JPEG images it works with other file formats like Tiff, PNG, RAW and AVI for movies.
iTag is a freeware for windows, requires Microsoft .Net Framework. Download iTag.