#6 - one of many ways to do this, is to install a sFTP server on your PC and a sFTP client on your N900. Or you can use ftp from command line. I believe you can also copy files via Ovi Suite, though within limitations.

#11 - my experience is that battery life actually has increased throughout the phone's life. However, if I ever leave home with the application manager open, battery will be flat soon enough. I am sure that goes for any software that idle poorly. Anyway, I feel that the battery life is quite acceptable for the class of device it is. I used to have an iPaq PDA and it would last about an hour.

I just wish the N900 would be less picky about what source it will choose to charge from at any given time.