BertieBaggio writes "I am a medical student at the end of an academic year trying to get my notes organised. I'm looking for a software document organisation system to organise a mix of text notes, journal articles, diagrams and scans. Ideally such a system would permit full-text and metadata search, multiple categorisations (eg tags), preserve the underlying files and be cross-platform (Linux/Windows/OS X). While I'm not averse to paying for such a complex solution, ideally the software would be FOSS so that extension or migration are possible if necessary. Desktop search (eg Google Desktop) probably does 90% of what I want apart from multiple categorisations, which is the feature I'm most interested in. Searching turned up a similar question over at 43folders which pointed me in the direction of Papers and DevonThink, but these are OS X only and seem to be aimed more at academic paper organisation. What recommendations does the Slashdot community have for categorising and organising a heterogeneous mix of files?"