Virtually nothing yet, I have only had it a week or so.
I have installed a couple of text editors, maemo mapper, the C++ build tools, ssh, numpty physics.
Apart from ssh, I would have thought that the other stuff wouldn't be doing much unless I ran it.
It was second hand, although the previous user was far from technical (I suspect they sold it as it wasn't windows, as there were a few .exe files in download), so I doubt they put anything on it.

The battery life on the 770 was good, so I was suprised at how bad the 810 is.