Web Based Competitive Intelligence Tools

Google Alerts

Google alerts lets you track competitor's company, their employees, product launches,new features, blogs, public profiles, photos,videos and more.

Yahoo Site Explorer

You can find who is linking to your competitors using Yahoo Site Explorer

SocialMention

By entering your competitor's name or keyword SocialMention will help you track how many times the term was mentioned in different in blogs and social media websites and it allows you to export this information.

Twitter

You can follow your competitors and their employees on Twitter. You could also follow the people your competitors follow.

Twitter Search

You can create and save twitter searches to track competitors keywords, product names and more.

Quarkbase

By submitting your competitors URL quarkbase lists you the most popular pages of your comeptitors and the websites where they have been distributed and the number of subscribers and more.

Compete

Compete lets you know the unique visitors, keywords to a particular website.

SEO for Firefox

Firefox plugin from Aaron Wall that gives you information on a site's PageRank, number of links at a certain page, popularity in social media, directory listing and more.

copernic.com

Copernic will search for new content on your competitor's web pages and then sends you an email on what is changed(keywords, new product pages, etc).