I have many PDF files ( scientific books, lecture notes printed from powerpoint presentations and various other resources like old NASA reports without digital descriptor (DOI) ).
For scientific papers with DOI I use Mendeley, which is great for that purposes. It is especially god for exporting citations to BibTeX. But for this other PDFs like books and presentations it is not ideal and it mess-up my database. I do not want to cite these documents anywhere, so I do not need Mendeley reference management functionality here. Also, I don't like that Mendeley copy the files to his own library, which takes disk space (some of the files are BIG like 100 MB each file ). It makes Mendelay useless for organization of PDFs e.g. on USB-flash disk.
I want to organize this other PDFs in a similar manner I organized images in old ACDsee 3.0. Should be a combination of file browser and very fast PDF viewer. It would show a view of the .pdf file in some side panel instantly after I move the cursor over it. Maybe ideal would be just a PDF-viewer plug-in for file browser ( e.g. for Nautilus).
Organization of pdf-files should be done by standard file-manager operation (rename file, delete from disk, move between regular disk folders). It should not depend on some special internal database or library of the program. The organizational structure created by the program should be possible to browse by standard file manager even after when I uninstall the program.
and should be for Linux.