Experiments with chocolate...

But can you measure the wavelength?

http://www.wired.com/geekdad/2010/02/leftover-valentines-chocolate-use-it-to-measure-the-speed-of-light/

N-body for free

Back in the day I wrote N-body code based on the Barnes-Hut algorithm. At the time you could get a GRAPE board to do the sums very fast:

http://en.wikipedia.org/wiki/Gravity_Pipe

Now it comes "free" in an iMac with a halfway decent graphic card:

http://developer.apple.com/mac/library/samplecode/OpenCL_NBody_Simulation_Example/index.html

Too much spare time?

Try

http://neverball.org/

to soak it up. I'm busy trying not to.

And I thought that they were taking the ....

http://www.phenix-online.org/documentation/ligand_identification.htm

Says it will test 200 common ligands. Awesome!

So here's where the latest CCTBX can be found

Includes loads of neat stuff, source down at the bottom...

http://cci.lbl.gov/cctbx_build/all.html

Home brew microcontroller

Want to play!

http://www.arduino.cc/

When is H = h, k, l in reflecting position?

Start here!

http://mathworld.wolfram.com/Circle-CircleIntersection.html

(pointer from Labelit source, more generally useful though)