A friend described this puzzle to me and I enjoyed it so much that I just had to write a script so that I could play it more.

The rules of this puzzle are simple. Cells can be in one of three states:

An UNSHADED (white) cell means that you have not considered this cell yet.
A DARK GREY SHADED cell means that the sum of the dark grey shaded cells in that row and column must equal the number in that cell.
A LIGHT GREY SHADED cell means that the sum of the dark grey shaded cells in all the connected cells must equal the number in that cell.

I Hope you Enjoy