This demo search engine allows you to query ~130K articles from the Stack Exchange / Programmers data dump using an Erlang implementation of the WAND / max_score evaluation stategy for Top-K Queries. Original paper can be found here: <a href="http://fontoura.org/papers/vldb2011.pdf" rel="nofollow">http://fontoura.org/papers/vldb2011.pdf</a>