SunUpDown 1.3 - Requires NOS 2.0. SunUpDown calculates for a choosen city:

the sun rise for a specific day, sun set for a specific day, longest day in a year

shortest day in a year. Cities are picked from the Cities soup. On idle time it determines the longest and shortest day in the year. Use the chart checkbox to draw a chart. The required data for this chart is also calculated on idle. So you can see it getting better and better.