1. Make magazine’s videos and podcasts (blog.makezine.com/podcast) have dozens of weekend projects, some macho, some crafty, for the DIY-minded.
2. The Orwell Diaries (orwelldiaries.wordpress.com) publish George Orwell’s domestic and political diaries as a blog, exactly 70 years after they were originally written.
3. Everything on iTunes (apple.com/itunes) is free, amazing given that it offers recordings of lectures from some of the world’s most venerable institutions (Yale, Moma, Oxford, Tate).
4. The Atlas Obscura (atlasobscura.com) is a compendium of eccentric places, with an accent on the macabre, that won’t make it into traditional travel guides.
5. How Stuff Works (howstuffworks.com), the creation of one Marshall Brain, aims to explain everything from DNA coding to car transmission problems in simple articles and videos.
6. Whether for learning essential phrases in Albanian, or taking up a language more seriously, BBC Language (bbc.co.uk/languages) can’t be beaten.
7. The National Geographic (nationalgeographic.com) is full of startling photography and mind-expanding writing on space, the environment, animals, even world music.
8. The Encyclopedia Smithsonian (si.edu/Encyclopedia_SI) doesn’t aim for comprehensiveness, but its idiosyncratic pages, on subjects as diverse as aeronautics and zoology, are high-quality stuff.
9. Academic Earth (academicearth.org) presents video lectures from Ivy League universities and their west coast equivalents without the $75,000 (£45,000) fees.
10. The Encyclopedia of Life (eol.org) is a giant work in progress: the idea is to generate a page on every species known to science; they’ve got more than 160,000 already.
11. Fora.tv (fora.tv) amasses video from public events and colloquia, from Alicia Silverstone talking about veganism at a bookshop to Noam Chomsky on language at the Commonwealth Club.
12. What Should I Read Next? (whatshouldireadnext.com) suggests ideas for books you should read based on whatever you read last. Entertaining, if hit-and-miss.
13. Get High Now (gethighnow.com) isn’t an outlet for dubious internet pharmaceuticals. Rather, it’s a brilliantly designed (or disguised) science site, explaining optical and audio illusions.
14. Mental Floss (mentalfloss.com), full of lists and trivia, will please both the pub-quiz general knowledge aficionado and the more sophisticated science junkie.
15. Strange Maps (strangemaps.wordpress.com) collects cartographic curiosities, mapping things like the place in the United States farthest from a McDonald’s.
16. Issuu (issuu.com) is a hub for online magazine publication. You get slick indie music mags like Urb, and niche publications like Teen Piano (coverline: ‘What your teacher actually thinks’).