I'm trying to keep my dock simple - just Chrome, MacVim, and the terminal. Is there a way to run iTunes without it being in the dock (i.e. just show the icon in the menu bar)?
The only way for an application to not appear in the dock (while also keeping the menu bar) is for the developers to place that functionality into it. I don't use my dock as a launcher, using Butler instead (which is a dockless application, btw).
You might try backing up a step and asking why you want to remove the iTunes from the dock and see if there's another solution. For example, I often listen to tunes on my iPhone rather than iTunes. If it's to keep the dock clean, try a different launcher than the dock and hide the dock instead.
From HERE. I have not personally tried it with iTunes, but it does work with some applications.
If you'd like to have an application running, but without a dock icon, there's a
way achieve this by modifying the application's plist file.
Open a terminal session, and first navigate to the "Contents" folder of the
application you'd like to modify (note - you may want to make a backup of the app
first, especially if it's one of the Apple-installed applications). This example
uses Key Caps:
Now, edit the Info.plist file:
You can use vi, pico, or emacs to do the editing.
Just before the closing Just before the closing </dict> tag, add
Save the edited Info.plist, then launch iTunes from the GUI
(your application foler). If your edit was successful, you should see iTunes,
but no icon in the dock.
Two things come close: you can (in Finder) select the iTunes application and 'get info', then paste a new icon over the icon (at top of the info window). The trick is, you use a selected patch of your desktop background picture as the icon (open the desktop picture in Preview, select a patch and copy). Or, to put items in the dock that don't take up space until you click them, but are always easy to locate without navigating folders, make a folder and put aliases of applications and such into it. Then, drag the folder to the dock, where a single click on the icon of the folder will show all the contents.