Hiding the xScope Dock icon
As of version 3.0.1, you can hide xScope's Dock icon using a command-line preference. Be aware that once you remove the Dock icon, your menubar will also disappear (making many features of xScope inaccessible.) This configuration is also not officially supported by the Iconfactory so if you have any problems with it, we'll just suggest for you turn the Dock icon back on.
Hide Dock Icon
First, quit xScope and open a Terminal window. After you get a command prompt, enter these commands:
defaults write com.artissoftware.mac.xScope generalShowDockIcon 0 defaults write com.artissoftware.xScope generalShowDockIcon 0
Then restart xScope and the Dock icon should be gone.
Restore Dock Icon
To restore the Dock icon, quit xScope then use the following commands in a Terminal:
defaults delete com.artissoftware.mac.xScope generalShowDockIcon defaults delete com.artissoftware.xScope generalShowDockIcon
If you choose to hide the dock icon in xScope, and have xScope in your startup items, it can sometimes cause the dock two display two icons. See this article for more information: http://support.iconfactory.com/kb/xscope/why-i-am-seeing-two-xscope-icons-in-my-dock