Shift+End Combo on OS X Lion
There is a default key binding to perform this function: shift +  ⌃ (control) + →.

If this won't serve, you may be interesting in Jacob Rus: Customizing the Cocoa Text System which provides instructions for creating your own keybindings dictionary.

See also:
Apple Mac OS X Developer Library:Text System Defaults and Key Bindings
Ask Different: DefaultKeyBinding.dict - old-style NeXT format vs XML plist format