From organizing thoughts to organizing files.

I'm trying to find a tool that will link files together based on context rather then just a keyword search. For example if I were to look at a products pdf file the program would also suggest perhaps its pricelist, emails, other PDFs from the same vendor or PDFs of similiar products.

I know it does not go directly to GTD in the sense of kGTD or similiar but would speed up completing certian steps involved at work, thus removing those steps from my list :)