This site's product catalog is powered by K2 with extensive template modifications and some integrations with other plugins/components.The catalog supports e-commerce ( currently not enabled ) by integrating with simplecaddy.. there's also a simple gallery addition to it as well.On the back-end I've written my own component that allows our client to take a spreadsheet, upload it and have it entirely rebuild the entire category/item structure in just a few seconds.Then finally we built an interactive product finder that ties in to the catalog as well.K2 is awesome!  We simply couldn't have done it this easily without K2, we'd have had to look at existing catalog solutions and then modify it to suit our needs.. K2 was a much better starting point.-
www.bitstormweb.com