The PoincareClock applet provide not only time : This spherical clock simulate a polarization modulation : Linearly polarized light is coming through retarder (birefringent plate). Assuming neutral lines of the retarder rotating along the seconds, then linear light come out rotating 4 times faster with green color in the equator plane of Poincaré space and circular polarized light is coming up and down to the poles in red, twice during a round for the seconds (i.e. one minute). Othewise, this an enhancement of one java example from SUN : The clock applet now has three parameters; the background color (bgcolor), the main foreground color (the hands and dial) (fgcolor1) and the secondary foreground color (the seconds hand and numbers) (fgcolor2). These three parameters are hexadecimal RGB numbers (like the ones used for the body bgcolor tag in HTML). For example:
<applet code="Clock.class" width=220 height=180>
<param name=bgcolor value="000000">
<param name=fgcolor1 value="ff0000">
<param name=fgcolor2 value="ff00ff">
would give you a black background, a red dial and hands, and purple numbers.
For those who don't convert to hexadecimal easily, here are some common values: