Some may have seen this but i found it most interesting and fun as well, it is basically a simulation where you have to range objects and then try to hit them taking into account wind:

http://www.shooterready.com/lrsdemohi.html

There is a tutorial on the ranging if, like me, you haven't done it before:

http://www.shooterready.com/mildot.html

Unfortunately we can't get the software outside of the good old USA as they are frightened we will use it against them.