I'm actually in awe that he corresponded with you, even if disappearing after a while. But don't read too much into his silence, it might not be that he took offense. I've noticed in myself and others that we can have the intent to keep a conversation going, but every opportunity comes at the "wrong time" or there's some idea that I gotta develop more before I write about it, or too tired or something or something. Days of procrastination turn into weeks, months, and then you've forgotten about it.

You might want to gently prod him but, obviously, not too frequently!

I've dwelt often on some of the other ideas in Xanadu and how they could be accomplished, particularly of how to maintain authorship, future revisions and bi-directional links. My use of HTTP referrers was a hack and depended on someone explicitly following the link in a browser (and not suppressing the referrer, which I think some privacy software does). I don't know how Nelson or other Xanadu engineers approached it, but for a while I was contemplating things like an extension to UTF-8 that could piggy-back unique identifiers in the last character of each word, or some other semantically independent sequence of characters.

In some of the UI mock-ups (or prototypes) I've seen, I disagree somewhat with the documents floating in 3D space and the lines connecting references. It looks too busy and messy to me, a great demo but not something I'd want to work with day-to-day. Jef Raskin's prototypes of zoomable UIs looks a little bit better, but with too much zooming.

A few years ago I was inspired to get a foot pedal for my computer. There was one company that sold guitar FX pedals with a USB adaptor that translated a foot-press to any keyboard combo you wanted. I programmed it to implement the keyboard shortcut for "Mission Control" on Mac OS X. It actually kinda works, as long as you get used to it.

Tap with the foot and see every open document zoom into view, tap again and it zooms back to what you were working on. Alas, I couldn't get myself into the habit, because I just didn't multitask that much. With a different UI, though, I can see it being more effective. The problem, as I see it, is that Mission Control doesn't prioritize what it zooms out to, it's just Expose on steroids.

But what if, when I tap my foot on the pedal, it zooms out to the documents I access most frequently, plus the most recent browser history. That might be better.

I also keep wanting to detach Hubski/Reddit-like link collections from the browser window and make each link and discussion thread its own high-level object on the desktop. Tap my foot and I zoom out to see all the links, tap again and I zoom back on the page or thread I was focusing on. I want to stitch my own work into that tapestry, so local private documents live in the same space as public pages on the Internet.

To the guy who invented those Flash/Java/Javascript "tag clouds", I want to grab him by the shoulders and shake him good and hard. "No! You made it useless! Take it out of the browser and group them semantically, make it part of the desktop, and clicking doesn't go to a new page but expand the contents indefinitely!"

I keep taking detours into the "Developer" category on the App Store to see if anyone has done this (or worse, to the ambiguous, nebulous, catch-all "Productivity" section). I want to develop, or see someone else develop, a folding text editor that captures everything, but not in a stiff cut-n-paste way like Evernote. Something that uses passive data-entry to organize everything automatically. When I try out "Mind mapping" software I get frustrated and pissed off: I have to specify everything myself.

Some of those ideas come from, or were triggered by Xanadu. Boy, it's been a long time since that Wired article ;-)