We use FAST ESP to power a large industrial search engine listing over 1 million companies and over 3 million indexed documents and receiving millions of visitors every month. I have been working with ESP since 2003 (then known as FDS 3.2).
FAST ESP is extremely flexible and can deal with indexing many document types (html, pdf, word, etc). It has a very robust crawler for web documents and you can use their intermediary FastXML format to load custom document formats into the system or use their Content APIs. Continue reading “FAST ESP Overview”