is there a possibilitie that when I plug in a usb into my computer an icon with access to it will appear in the dock and when I unplug it the icon disappears?

maybe you can try to do a shortcut to that drive ? but i don't think it will dissapear (in object dock it doesn't dissapear). or maybe ther's a docklet available somewhere ?

Well Suck you can get more information on adding shortcuts to Rocket Dock from the offecial site for the application

Punk Software Forums for Rocket Dock

You can register yourself there and post your question there, they'll definitly help you wheher you say or not that we sent you

did u ever find a way to do this?