Khan Academy Computer Science
youtube.com
youtube.com
Edit: Already (on his second day of making videos) he is starting to branch into algorithms: http://www.youtube.com/watch?v=lCzQvQr8Utw
Someone who wants to learn CS can find no shortage of introductory material on programming (along with communities of people to do it with), stuff on algorithms and data structures and the relevant math, more advanced topics -- it's like being offered a free education at a really good college, for people who are willing to do the work.
I would really like for other subjects to become similarly open to interested people over the internet. CS has definitely been leading the way here. Wouldn't it be amazing if people in (say) archaeology, or botany, had a fraction of the free resources and helpful communities that hackers have had online for years?