Shift+End Combo on OS X Lion How can I change the settings for OS X Lion so that the combination of Shift+End results in the selection of text from the current cursor position to the end of the current line?  Specifically, I would like to be able to do this in Firefox, but if there is a general method that works for most/all applications, that would be ideal.
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