Did you know that you can update your Twitter profile from Technorati.com (and Facebook status, other update feeds for that matter)?
I may be biased given my loose association with Technorati (!!), but this has instantly become one of my favorite social media utilities. I already enjoy tweeting and publishing a steady stream of Twitter and Facebook updates, largely because I like commenting on topics of the day -- industry-related trends, political issues and interesting news of all sorts. So having the ability to browse blog posts or other content on Technorati and then write a comment that auto-tweets is both fun and useful.
For example, check out my blog profile and Twitter "blog" profile on Technorati. Each profile page has a "Reader Review", where I've detailed useful "how to" details on blurbing-auto-tweeting and claiming your Twitter profile as a blog, respectively. As I mentioned earlier, I also like to comment on issues of the day -- searching Technorati for blog posts about a news story, commenting on it and automatically tweeting the comment and post page on Twitter and Facebook.
If you're writing about something you're an expert on, you can also provide links to useful related content; if you're the author of that comment, there's an obvious SEO benefit as well.