I have Flash disabled in my desktop browsers and enable it rarely (I had to install it because I wanted to watch Sherlock Holmes, and this TV website required Flash, damn them, why don't they offer HTML 5?).
I don't know whether I have Flash on N900 - I haven't needed it, and if it is installed here, I'll look whether it can be uninstalled.
I don't have Silverlight at all - and I will not install it even if Microsoft says that it's made an open standard (like it did with docx).

When will HTML 5 become the standard for interactive webpages, audio and video playing? When will SVG and MathML be as common as PNG is today?

Of course, it's good to have Gnash along with Flash and Moonlight along with Silverlight, but I consider Sudoku Solver more justified installation than any of these four above-mentioned programs.

Good day, and don't be angry at my bias.

Good luck with porting Moonlight to Maemo/MeeGo.