this site isn't exclusive to theoretical physics. most of the material is broad. It's not until the later topics that it becomes more theoretical: general relativity, super gravity, string theory...

physics may also interest those who don't want to be come any type of physicist, hence the popularity of television shows like Cosmos, etc. for those that want to dive into something a little more technical, but very approachable, there are the feynman lectures, which are freely available online here: http://www.feynmanlectures.caltech.edu/