Is there any software that allows me to experiment with solar sail models?
I want to try models of sails of different sizes, different positions around the Solar System, and different trajectories.
Martin Schweiger's "Orbiter" (a freely downloadable simulation/game) has basic radiation pressure simulation and apparently a solar sail scenario which would be the first thing to try. (I haven't tried radiation pressure simulation at all though.)
For example see a vague mention of this ability here:
(Hint: if the solar sail doesn't have any attitude controls, point it coarsely using the Scenario Editor to alter pitch/roll/yaw, and kill any unwanted angular velocity if necessary.)
By default it starts with a circular orbit at 1 AU, and remains in that plane. It is not quite what you are after, but does allow one to change orientation and lightness number.