Tweetbeep is basically like Google Alerts for Twitter. It’s a free web-based service that lets you get notified via e-mail whenever someone mentions a word, name or phrase on Twitter. Find out immediately when someone tweets (posts) your name, company, or website address on Twitter, even if they use a URL-shortening service like TinyURL.
Note: they are growing very fast and the site has been offline as of late.
Twitstat shows the most popular words of the last 500 tweets of people tracked by @twitstat. Get automatic hourly updates of the Top 10 by following @twitgeistr
Of course, if you haven’t already heard, Twitter just re-launched their Twitter People Search Tool which finally allows you to find people by name even when their Twitter account username is an alias.
I recommend you check out all of the above, but so far, I still find Twitter’s search tool to be the best search tool at finding the most relevant social media conversations related to my clients’ brands and my own fields of interest.