Semantic Web Getting Real
The company I work for, Garlik has two products that are run off semantic web technology. DataPatrol (for pay) and QDOS (free, in beta).
We use RDF stores instead of databases in some places as they are very good at representing graph structures, which are a real pain to real with in SQL. You often hear the "what can RDF do that SQL can't" type arguments, which are all just nonsense. What can SQL do that a field database, or a bunch of flat files can't? It's all about what you can do easily enough that you will be bothered to do it.
A fully normalised SQL database has many of the attributes of an RDF store, but
a) when was the last time you saw one in production use?
b) how much of a pain was it to write big queries with outer joins?
RDF + SPARQL makes that kind of thing trivial, and has other fringe side benefits (better standardisation, data portability) that you don't get with SQL.
I guess it shouldn't be a surprise to see the comments consisting of the usual round of more-or-less irrelevant jokes and snide commentary - this is Slashdot after all - but I can't help responding.