I'm a heavy user of Shannon Whitley's SPIURL public service that offers easy links to Twitter portraits, so I was very interested to hear about a new project, Real-Time Chatterbox. It's a website widget that lists the latest Twitter comments that mention a keyword you specify. This is a great way of showing social proof to potential users if you search on your company name. To help weed out offensive comment Shannon lets you apply a black list of foul language, and so far I've been very happy with the results.
I've added this to the front page of twitter.mailana.com, and if you're interested in a free and easy way to engage your users, I highly recommend you check it out too.