TED: http://www.ted.com/. Really awesome website. It contains all sorts of amazing talks on video.
Skeptic’s Guide To The Universe: http://www.theskepticsguide.org/sgublog/. Blog written by the cast of the Skeptic’s Guide to the Universe, an excellent skeptical podcast.
Science Daily: http://www.sciencedaily.com/. Good source of science news stories. Some of their stories aren’t skeptical enough, but it’s still a good site.
Science Blogs: http://scienceblogs.com/. A website with links to over 75 excellent science blogs.
Science Based Medicine: http://www.sciencebasedmedicine.org/. Excellent blog about science, skepticism, and medicine.
Neurologica: http://www.theness.com/neurologicablog/. Awesome blog about neuroscience.
Skeptic’s Dictionary: http://www.skepdic.com/. The ultimate resource for checking out all far-fetched claims. If it sounds suspicious, check here first.
Surgeonsblog: http://surgeonsblog.blogspot.com/. One of my favorite blogs, run by a retired surgeon.
MIT OpenCourseWare: http://ocw.mit.edu/OcwWeb/web/home/home/index.htm. Lot’s of free college courses from MIT.
PubMed: http://www.ncbi.nlm.nih.gov/pubmed/. Provides free access to the abstracts of thousands of life science and medicine research publications.