[adamors]

Have you looked into KDE? KDE has a pretty complex file search/tag system called Nepomuk: http://userbase.kde.org/Nepomuk

[venomsnake]

Nepomuk is indexer, and I am not sure it starts indexing on volume mount, also not sure if it is hooked into fnotify. Everything is reads straight from the NTFS journal - it is really smart little utility that has become my main launcher for everything. But I have not found current in development project that could be used like that - rlocate was closest but it is dead from 3 years.

[adamors]

Nepomuk is not the indexer, Strigi is. And Strigi has inotify support AFAIK.

EDIT: This is an older post, but I think it shows exactly that: http://www.afiestas.org/nepomuk-is-not-fast-is-instant/