There's more and more usage of Twitter at events. If you're considering it, or looking to embed it onto a blog or webpage, consider Twitterfountain. Here's an example of how it works, using my tweets. It can also pull from pictures tagged in Flickr. Great to use with your event hashtag (consider posting it on your website for the conversation to be watched before, during & after the event).
The look & feel of it is customizable. Really nice tool.