I was thinking it would be cool to have a simple, easy to use website that you could use as a whiteboard - some place you could go with your browser and type stuff for others to see, allow others to edit it, and immediately see their edits. It seemed like this would be a useful tool for teams collaborating over distances, or even conducting an online programming job interview - talk to the person you're interviewing via Skype, telephone, or chat, and have them write an algorithm on the virtual whiteboard so that you can see them as they're progressing. Beats having to shell out for hotels and airplane tickets, especially if it's for someone who doesn't really know how to code. :)

A quick web search reveals that such tools already exist, and I tried a few of them. The best one for my needs turned out to be skrbl. It's straightforward - creating a new whiteboard session takes just one click and requires no registration. Anyone can join simply by sharing with them the session URL or session ID. It works in IE6 and IE7 (as opposed to not working in them), it doesn't require Flash, it isn't heavy on the CPU, and it's responsive. Great job!

Other sites I wasn't as satisfied with included Vyew, which is almost as easy to use as skrbl, but is less responsive, makes it less easy to manage and edit text, tends to lose characters on input, uses Flash, complains about IE7 on Vista, and badgers the user to install Firefox instead. Meh.

Also interesting is GE's Imagination Cubed, which is simple and easy to use enough but requires Flash, is much more drawing than text-oriented, and starts to burn an awful lot of CPU once you've drawn a big enough picture.