[curstpriest]

I think he means that he wants to send stuff over wifi (probably NFS or samba) possibly ftp.

There is no way to do this that is supported by the default firmware. Someone could write a daemon and compile some binaries to do it if they really wanted to, but it's honestly not worth it. Just use the mail feature since it will send over wifi if you have k3. If you have a K2 or DX however, you are out of luck with the 3g radio =X

If you do have a 3g only model, you could do the following:

Run a simple webserver (such as thttpd on a router flashed to wrt based firmware) or get hosting somewhere with apache or whatever.

Upload your books to your server directory, and then open the kindle browser and download them from your webserver. You can protect the webserver directory if you like with a password.. k2 and k3 browser supports password authentication, just set up your .htaccess file on the webserver, though IDK why you would need to do this if it's just for yourself (more useful if you are sharing with your family/friends).