Every time I am bored, I discover an interesting new website! But how? Well, I just stumble upon them!
Just visit StumbleUpon and install the tool-bar plug-in for your browser. Thereafter, every time you click on the Stumble! button in your browser, a random website is shown based on your interests (which you choose from a list of subjects shown by StumbleUpon during the free registration process -- you can even change these settings later.)
You can even give websites a thumbs up or thumbs down, depending on how good it is. This helps StumbeUpon to serve up interesting websites -- after all, you got an interesting website only because the crowd shared its views about websites they saw, so do your part and rate the websites you see :-)