Ask HN: With a single site per comment, which sites do you visit regularly?
That way, you can upvote your favorites instead of posting a new, unique combination.
Great for physics and math, both homework, casual questions and more advanced stuff. Large number of active professors, phd studens etc.
(weird these hadn't been added)
It might have been better to ask for the sites we think are coolest, even if we don't visit them regularly.
The zeitgeist of the country. A much cleaner web page than most things he links to.
My fix for back pain and a host of other problems.