Well, Alexa now has one of the most used web site ranking systems.
You're reading this 'cause you agree that Alexa.com is a useful site for webmasters, right? Come on man! Well, that's my sentiment.
If you still need convincing, then use the toolbar for a week or so. Click the alexa icon found on the top right of the browser, to see if you like anything it is telling you.
While you are doing that, good golly, here are 4 ways to use Alexa, to improve your webmaster work:
1. Pay $9.95 a month, for access to more than 5 Sites Linkin In. The small fee is worth it and comes as an auto-debit to your PayPal or other method. You can always cancel at anytime.
What you do is look up a popular site in your site's theme, then view their Sites Linking In, then visit those pages, to see if you can can your link on those pages. The benefit of focusing on those pages is they are already showing up as Alexa friendly links.
2. Install the Alexa extension for Google Chrome. This is not a right-to-left browser length toolbar, but only shows up as a little icon that you click to view the following stats: Alexa Traffic Rank, Sites Linking In, a link to the site's Wayback Machine, and the speed of the site.
Want more info? See Funthings @ bitoffun and Matt @ namepros.
3. Use the Alexa Traffic Rank to buy advertising and do fair link exchanges.
4. Verify your website, add a logo, contact and other info to the alexa site info stats.