- A Logic Calculator. Test if an argument is valid or invalid. Generate truth tables. Find counterexamples. etc.
- Definitions from Quine's
*Mathematical Logic*. See how basic mathematical constructs can be reduced to statements about sets and classes. - Possible Worlds Semantics for Second-Order Modal Logic. An unfinished attempt to define logic in terms of possible worlds.
- Probability in Light of Independent Testimony for Mutually Exclusive Possibilities. How to calculate probability from conflicting and corroborating testimony (under certain circumstances).

- Javascript drum machine.
- Musical Interval Explorer. Hear arbitrary harmonic intervals and chords in any tuning in your browser.
- Musical Ratio Explorer. Analyze ratios. Calculate their prime factors. Calculate intervals between ratios. Visualize them within a musical scale.

- A digital clock with invented hexadecimal digits
- Draw a path, exchanging the time dimension for width or height
- My Blog. Rarely updated. Miscellaneous topics.