Miscellaneous
http://www.futilitycloset.com/2012/09/14/pen-guidance/
Futility Closet: a real philomathic blog.
http://www.cthreepo.com/lab/math1.shtml/
Space Math; free calculators tailored to common sci-fi events.
http://www.spiders.us/articles/identification/
Spider Identification guide.
http://www.scientificpsychic.com/etc/timeline/timeline.html
Timeline of Earth, highlighting many geographical, astronomical, biological, and other events. First-rate broad scope launching point for worldbuilding concepts.
http://www.metaresearch.org/cosmology/speed_of_gravity.asp
1998 paper on the Speed of Gravity. Outdated? Incorrect? I’ll stick with “fascinating,” at least until the graviton is pinned down further. I love everything about the idea of superluminal gravitonic impacts imparting a negative inertial charge — think of the sci-fi applications.
American Science & Surplus is almost worth reading for the colorful item descriptions alone.
http://www.thebodyonline.net/about_info.php
A serious and surprisingly free anatomical guide, including some radiology.
Possibly the best link I’ll ever put on here, just in case you didn’t know of TED Talks before now. Subtitles are available!
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