Site Launcher is a Firefox add-on that adds this functionality to the web browser. It does that in two ways. The first is by proving access [via CTRL SPACE] to an overlay menu which displays the configured websites that can be launched from there. Each website is assigned a single key on the keyboard which has to be pressed to launch it.

The second method [via ALT SHIFT KEY] is there for keyboard junkies who prefer to press one hotkey for the same effect. Adding websites to the Firefox extension is easy. It is possible to open the Site Launcher Manager right away and add websites manually or add websites directly when they are loaded in the active tab.

It is furthermore possible to change the default hotkeys if other combinations suite you better.

It does not really matter which way you choose as you can modify all parameters afterwards. You have to enter a key, a title and an url to add a new website to the application. Each key can only be added once to Site Launcher. There is also only room for lower case characters.

Each website that is opened this way will be opened in a new tab by default. This behavior can be changed in the extensive options. It is possible to change the appearance of the menu and other functionality in there.