Bob Jenkins' Web Site SpookyHash is production. It's a 128-bit hash that hashes about 3 bytes per cycled (on 64-bit platforms). It's reasonably fast for short keys too. I just corrected some typedefs to make it a little more portable. Google's CityHash has a similar spec (also 128-bit results). On machines with a crc32-instruction, they say it is 6 bytes per cycle. I've never seen anything that fast. (It's not that fast on my machine, which doesn't have a crc32 instruction.) It passes my frog test for at least 70 bits.

Table of Contents (internal links):

Hashing

Here's a hash table, code for perfect hashing, a good hash function for hash table lookup, a FAQ, some theory, and code to search for new hash functions. I tried designing block ciphers and finding characteristics. I had an article published in Dr. Dobb's in September 1997.

Randomness

Have the cryptographic pseudorandom number generator ISAAC, a small noncryptographic pseudorandom number generator, a prize for breaking ISAAC, and ISAAC's background and theory. Also take some tests for randomness, and a table of orders of magnitude. Here are also some protocols and a unit vector generator.

Collections

See some skits from Boy Scouts, SQL tricks from Oracle, near-future speculations, some paper airplanes, some recipies, and some cartoons that I wrote in college.

Math

Look into pentagonal tiles, formulae for n-body orbit simulations, code for the HOMFLY knot polynomial, voting methods, choosing random passwords, jenny for pairwise testing, some error correction codes, a distributed HTML index, and a web page for choosing colors.

Physics

Consider perpetual motion machines, a dirigiped design, a scale model of the solar system, a page on exploring orbits with Java, Klemperer Rosettes, a simulation of Cruithne (a near-earth object), of figure-eight orbits, of binary star planetary orbits, a set of noncolliding orbits, some Dyson Swarms (pretty pictures!), some methods for the n-body problem, a description of the orbit applet used, and a tentative itzu world.

Home projects

See my half bath, a house design that will never be built, a dollhouse that did get built, some genealogical notes, and a roof rack for Justine's car.

Other

Here is my autobiography, a resume, a cong from the British Museum, a comparison of JPEG and JPEG 2000, a bit on software patents, my mom's art, and some early Bob photos. My wife Justine has a website too. Here are people I've encountered more than once.

• Search engines: Hum. Here's a chart of search engine market share.
• Usenet: Google groups answers the questions people tend to ask.
• Stock quotes: Yahoo has personalized portfolios.
• News: http://sciencedaily.com for science news, bing for newspaper news, the BBC for a non-US perspective, or the Onion for spoofs of it all.
• Relative's pages: my wife Justine, my mom's online art gallery.
• Translate English to/from Spanish,French,German,Italian,Portuguese.
• Specific stuff: near-earth objects, astronomy journals, the Encyclopedia of Integer Sequences, digital camera reviews, genealogical research, and Rubik's Cube.

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