PhotoSynth requires a Windows-only plug-in that also lets you create synths, but the results depend on the number and quality of your photos. Microsoft suggests to "start by taking a panorama of your scene, then move around and take more photos from different angles and positions. When moving around objects, try to get one photo every 25 degrees or so. That will make the synth work better."
There are some interesting places that can be explored, but this technology will become really useful in conjunction with geocoded photos from sites like Flickr or Panoramio. Google Maps already overlays photos from Panoramio, so the next step could be to combine these photos using "Panoramio Look Around", but the results won't be anywhere close to Photosynth.
{ via Data Mining Blog }