I have a large (approx. 25GB) collection of files I would like to host online for people to view or download. I have a spare computer I can use as a dedicated server for these files. I'm looking for a method of, or piece of software for, hosting my files where I can assign tags or keywords to the files, and people viewing my files online can search the collection via the tags.

By way of approximate solutions I've found so far, I see that there is software such as Collectorz.com or Readerware for creating databases of one's books / music / movies, and these databases can be searched by tags or keywords, and the databases can be made available and searchable online; this would suit my purposes except that my files are not necessarily books, music, or movies, and I want the files themselves accessible online, not a database describing my files.

A commercially-available solution like the ones above would be acceptable, but I'd prefer to have the whole setup under my control (i.e. I'd like to either implement it by hand, or use commercial software that doesn't rely on using the company's servers, paying them a continued fee, etc.).

The current extent of my internet experience is designing a few Google Sites, so I know there's a fair chance I won't understand the answers I receive, but I'm always happy to have a summer project :)