My company has built a nice business around solving this precise problem, although as a web app for internal use in an organisation rather than for organising a filesystem.
The key principle is to organise things by their description, not their position in some sort of filesystem.
If every field in your description allows multi-values, then you can put an object in multiple places. And if you can search and browse on any field, you can find it by subject, author, kind of information, and so on.
There are a few other clever ideas in there, but that's the key: Help users enter really good metadata, then use it to find things within a flat namespace.
This ties into what I've often thought about our computerized world, that it is mostly a matter of semantic differences, similarities, and identities that prove the mettle of any system considered 'productive'. If my semantic set and your set are generally coherent, we can get something done; if they are not, then we spend a lot of time trying to attain semantic equilibrium, before anything actually gets done according to the business purpose.
The tools that allow us to synchronize our own conceptual copy of the semantic universe in a way that produce a 'flow' between individuals, are the ones that mostly succeed.
Haplo seems to do a good job of giving a small group the ability to construct a semantic set with a productive goal. I've looked at it for 5 minutes, and the only thing I can think to contribute is that I feel it would be of objective benefit to give more examples of how Haplo has granted a group enough self-awareness to actually get some work done. There is kind of a meta- sense to the product, which can either work for you, or against you. Showing how you can use Haplo to build a small business production/flow-line might make it a little more clear as to what particular problem you are solving.
Another thing is that the web is really quite functional, on the one hand, but boring on the other. I wonder how you might gamify Haplo ... Well, I have some idea's, anyway ..
Humans are very good at describing the world, and communicating through common vocabulary. The problem comes when you don't model the real world, but instead model your current business processes within a traditional database.
Haplo's data model encourages you to model the real world, using the normal shared vocabulary, then hang business processes on top. This eliminates the semantic problems.
Generally problems come when you try and squeeze your information into what's easy to create with SQL databases and the current crop of NoSQL document stores. We spent the time to build an object store which was capable of handling "information", rather than "data", and it makes an enormous difference.
Regarding examples, we're working on more overview documentation and some example applications.
As a company without investors, funded entirely by revenue from our customers, those customers have to take priority over building example applications. Our aim is to open source the majority of the work we're doing, and hopefully those will be good examples.
>model the real world .. shared vocabulary .. SQL databases .. object store .. good examples.
This is the crux of the challenge, I think. Anybody who doesn't know what a scone is, can't really sell it.
The modeling occurs at a word level, like .. as a dictionary .. and everything else is just baggage. Get everyone on the same page .. of the dictionary .. and you get a working group. Isn't software secondary to human interaction?
The key principle is to organise things by their description, not their position in some sort of filesystem.
If every field in your description allows multi-values, then you can put an object in multiple places. And if you can search and browse on any field, you can find it by subject, author, kind of information, and so on.
There are a few other clever ideas in there, but that's the key: Help users enter really good metadata, then use it to find things within a flat namespace.
It's open source: http://haplo.org
We're hiring developers to work in our London office: http://www.haplo-services.com/jobs