Directory of 3DS Browser sites.
Probably the site that started the 3DS (and I think DS) Browser scene. Has a whole bunch of apps.
A site that has some cool stuff, similar to 3DS paint. Has some really cool games though.
Jeff's Most Annoying Website
A website similar to the button, not really designed for the 3DS Browser but the core thing works with it. (and might be more annoying.)
A online PokeDex for the web browser, really neat and useful for when playing pokemon.