What wedda said - running wireshark will show you where you're sending data to, and where it's coming from. It won't tell you, as far as I know, however, what application is sending those packets, as far as I know.

I have "always ask" on, and it never asks to go online out of the blue. If I'm connected to the internet, it will check for updates, statuses, mail and whatnot, if I'm offline it remains offline untill I launch an application that needs internet, like the browser, then it asks if I want to connect. is yours working differently somehow?

being offline causes no problems whatsoever btw, ossipena.