Cocoa application licensing schemes are a contentious issue. Opinions on how, and whether, to protect your application from piracy vary widely; from the open source approach, which simply sidesteps the issue, to sophisticated public key encryption schemes. There are at least four pages on CocoaDev vigorously debating the pros and cons of each approach.

Assuming that you do want to copy protect your Cocoa app, choosing a licensing scheme in 2009 boils down to a small number of choices, as far as I could determine.

While working on feature requests for DateLine recently, I needed to add the ability to run the app Dockless - that is, without a menu bar or Dock icon.

XMRemoteImage is a simple project that demonstrates a way to update an NSImage from a high resolution graphic on the web.

A Cocoa source project using NSAppleScript to access iTunes artwork by track Persistent ID

Some free, creative commons licensed source code.