I would like to search my server (or even the entire local area network) for files with possibility of indexing (even the content of txt, pdf, ... files). I got suggested this link (http://serverfault.com/questions/4591/recommend-an-opensource-network-search-tool) while starting this question. Is it any opensource alternative ? The only other network search tool I know of is google desktop which was not really intended for servers.
Any other suggestion would be appreciated. Server is Linux debian squeeze 6.0 if that can help.