"Maurizio" wrote: could you tell us what these products are? We may get some more ideas by examining them.
The product I purchased and thought at first was fantastic was Topicscape. The user interface is very good for sorting and relocating files. Though there is a lot of work in getting the groupings and maintaining file lists. I am fidding Tabbles is much more usable.
Other programs link items that can be tagged to files, which I guess is more or less what Tabbles does but you work with the items not the files.
I purchased and mainly rely on Biblioscape which allows you to link bibliographic information to the files . It allows these to be tagged and also to have "vurtual folders" for files belonging to multiple copies. Twice in about five years I have had the tag information become currupted, which leaves me not wanting to rely on the tagging in this program.
The other program I use is Swift To-Do List allows files to be linked to items and these can then be sorted and aranged. Not Comparable to Tabbles, but I would like you to think about adding a to-do list window to Tabbles.