I've added a new search feature to my site that uses the Yahoo API to find related articles based on keywords. You can test it out at http://www.kinlan.co.uk/AjaxExperiments/AjaxTag. It's a work in progress, but more features are coming soon!
This blog post discusses the importance of balancing valuable content with helpful features. I currently offer content and features like Technorati tags, and plan to bring back related searches. The AJAX application I built helps create this value-added data, which I believe is key for reader engagement. I'm considering adding more data like citations and related searches, but I'm cautious about information overload. Maintaining these value-added sections is challenging (except for the now-easy Technorati tags). I'd love to hear your suggestions for other valuable data to include!