The Rosetta Clock
Here’s an applet I wrote that draws clocks in 5 different numeral systems. From the top row down, they are:
The first column is the hours, the second column is the minutes, and the third column is the seconds.
In the first 4 rows; a green dot represents a 1, a blue dot represents a 2, and a red dot represents a –1.
Source code: RosettaClock.scala
This is actually kind of useful for learning to count in the different systems. Each of the systems has some distinctive patterns which you recognize after a while. It’s also pretty neat to see them together though. For example, you can clearly see how skew binary and ternary start out together and then start to go their own ways when they reach 7.