I've never had a filing cabinet. Well, to be more precise, I've never used a filing cabinet properly, only to hold stuff that I don't want to look at.
Instead, all my experience of filing has been online - with Windows folders (which is great, because you can configure it exactly to your own logic, but falls down when other people are allowed to mess about with it) with document management systems like Hummingbird (which gets around the other-people-stuff-it-up thing, but allows no personal logic) and with bookmarks in my browser.
I've been experimenting with bookmarking sites, including the biggie, del.icio.us, and some that aren't as famous as YouTube, like simpy and furl. I've decided that my favoured option is Magnolia. I like the interface, they way that you get told who has bookmarked the same page as you, the presentation of the tag cloud. It's quite pretty and soothing.
What I want though is the best of both worlds - I want folders to categorise my bookmarks, not just tags. I want to treat it like a binder full of photocopying, with dividers and coloured tags. The Magnolia wiki shows that I'm not alone in this. Fingers crossed.
For other paper-lovers: a guide to making a notebook act like a PDA, from Creating Passionate Users.