Going beyond the obvious jokes about genitalia and advertisements (or both...), here are some ideas I had while playing with it.

* An enhanced WYSIWYG for online editors or blogs. You could eliminate the need to go to any back end to create or edit content. The pulldown above allows for custom templates to be used to populate the page with boilerplate, or to even change the theme used, and then exported to the website to be "published"

* Online collaboration of websites and content beyond Word and Google Docs. Because it acts as an overlay, you could make some comments or changes to a live site and send that to another designer or copyeditor without changing what other users see.

* Visual successor to Greasemonkey, allowing users to recreate a page as they see fit. These enhancements could be distributed to others for new widgets or themes for existing sites.

There already is a sort of visual successor to Greasemonkey: Stylish, at http://userstyles.org/. As Greasemonkey lets you write custom JavaScript, Stylish lets you write custom CSS. But it’s not exactly a tool for the masses, since you have to write CSS by hand. And you’re lucky if the site you’re styling has a clean enough DOM that plain CSS is enough – I drop to writing JS-enhanced CSS in Greasemonkey when the site has that problem.

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I like the generated HTML.

There also appear to be a couple blank 300x150 PNGs encoded as data URIs in the source?

Hm, blank ones? data URIs are how we store the drawings on the site, which are HTML5 canvas elements

Looks rad. Are you guys thinking about ways to integrate dynamic content?

Yes. We had an email collector for awhile but it wasn't being heavily used. Any good ideas for things to add?

1999 called ...

Except instead of asking for Netscape Navigator 4.0 or higher, I get an overlay saying "Please switch to Google Chrome to access the editor" when I try to use the demo

... then the paper would be covered with drawings of penises in the early stages, and giant advertisements in the later stages.

I came here to post this. The only way you could possibly have anonymous visual interactions on the internet without penises would probably be to create a "show us your penis" website, it would get trolled by people posting cats or something.

Or youtube comments.

Places like HN, Metafilter & The Economist, where the comments are not utter trash are rare on the net.

You wonder if this person goes to a movie and want everyone to talk all the way through.

This.

I wrote Goggles. http://goggles.sneakygcr.net

You turn the bookmarklet on and it overlays a transparent <canvas> on the web page you happen to be visiting.

Everybody gets a pen. It works just like multiplayer MS Paint.

Your comment is pretty accurate sometimes. ;)

So what? That will be a problem for Google to solve.