Tagging web images dynamically with roll-over labels -- where's the software?

I've been wanting to edit those photos to dynamically identify the plants rather than just list them. So, I'm looking all over for simple freeware software that allows me to identify items (objects or persons) in a photograph and tag them, as is done in Facebook (much to our chagrin, sometimes, after a bad hair day gets captured). And somehow, it doesn't seem to exist. The idea is a good one, and I'm sort of amazed, given the pace of Web 2.0 development, that it isn't possible to do yet.

You can tag whole photos with thematic tags (that relate to the whole file), and you can geocode photographs to identify where they were taken on a map (the basis for the fun of Panoramio, the map features of Flickr, GoogleEarth, as well as the images connected to Googlemaps). The latter is also, obviously, a label (or, if you prefer, piece of metadata) that applies to the whole photograph. Labeling component parts still seems out of reach outside the context of applications for Facebook.

I found an Eastern European-developed software called TagHim 1.0, but it's impossible to download. Their own website has, in fact, been suspended. Perhaps it's because they spammed most software review sites with the exact same content (in noticeably non-native English), including reference to Facebook. Or, maybe they violated the terms of use for their website host. I'm not sure.

TagHim even has a YouTube video of the developer demonstrating the software with his charming Slavic accent and misspelling of "Mickey" in his process of tagging a photograph of Mickey Mouse and Pluto. It looks, effectively, like exactly what I want. Simple, free, fast, effective. What's the holdup, folks? Does anybody know anything about this?