Here's a cool tool: Answer Tips (see the badge at the bottom of the sidebar). As of right now if you double click on any word on this blog that isn't a link a bubble will appear to teach you something. ;-)
I can think of scads of circumstances where this would be beneficial on my class blogs. For now, it's just here for a couple of days as I experiment with it ... I don't think the experimentation phase will last very long. ;-)
Thanks to Jan Nordgreen of Think Again! for the link.
Update: April 29, 2007
I've been thinking about how this tool works since I first saw it. I think it has tremendous implications for how we read, write and learn in a linked environment. Essentially, Answer Tips drenches every text posting to a blog or wiki in content. Every single word is clickable to learn; how to pronounce it, what it means, examples of it's use, explore the meaning in greater depth and more.
Part of learning in any domain involves acquiring the specific vocabulary associated with the content. The implications here for learning math, science, social studies, geography, English as another language, etc. are endless.
With a tool like this a teacher can simply publish a vocabulary list to the class blog and:
• assign the students to learn the meaning of each one, maybe test them on it in their next class.
• preview the content that will be covered in class the next day.
• ask students to post pictures of examples for each word (science, geography) to bring another modality to help solidify their learning.
• publish to a staff development blog where teachers can thrash out together the best way to teach a network of related concepts.
• ... add your ideas in the comments below. I'm sure there are many more I'm missing. ;-)