If you're a sucker for keyboard shortcuts, you're going to love SiteLauncher.
This simple Firefox add-on provides you with a selection of direct shortcuts to your favorite websites, so that you can access them even faster. You could say that SiteLauncher is in a way similar to the bookmarks bar, but this little app has some clear advantages: first, it has room for a lot more links and second, it can be triggered with the keyboard and hidden away after usage.
All you have to is launch the menu with a customizable key combination and select the website you want to access by hitting the correspondent letter. Another option is launching the website straight ahead with another shortcut, though this obviously requires you to memorize dozens of combinations. SiteLauncher already includes a few popular web pages to get you started.
The website list in SiteLauncher is nicely laid out on a semi-transparent window, which has a few configuration settings to tweak its behavior and appearance. The only limitation is that you can use just one letter per shortcut, so when you finish the whole alphabet, you're done.
SiteLauncher is a nicely designed shortcut menu that lets you access your most frequently used websites via customizable keyboard shortcuts.