Are typos slowing down you and your Web-surfing ways? If you are typo king or queen, give Nbar a whirl. It uses fuzzy string matching to guess the meaning behind incorrectly entered URLs in Firefox. For example, if you enter "hugg" in Firefox's URL bar (aka the Awesomebar), the extension will suggest The Huffington Post, should that be a site in your history.
The extension does not require a restart and provides two settings. The first, Search threshold, controls how many suggestions will appear in the drop-down menu as you type. The second, Word distance, adjusts the sensitivity of the extension to your typos. The higher the number you enter, the more forgiving the extension is to your typos.