Based on the old mnemonic trick of taking a real physical location that you know well, and associating memories with objects in that space. The digital version of this would be having files and data stored in a "physical" place - although they're not solid, they'd be tied to a single location.
Harder to organise, but I know several people who have completely filled their computer's desktop with shortcuts, because they don't like futzing around with folders. The folder metaphor isn't the be-all and end-all, there are times when it's appropriate and times when it's not. The metaphor of icons that are dragged around the screen is limited by available screen space - Project Tango gives you a house-sized (or even just room-sized) 3D space to play with, more than enough for all the files you could need to be immediately visible.
The main risk is that my virtual room could end up as messy as my real room.
I don't know how anyone could make money from this, but it would be really damn cool.