UncleMark is a teeny, tiny addon, with one simple goal: To allow a player to quickly mark targets, using just one key.
If you like the idea of Magic Marker, but find that it's too cumbersome, give UncleMark a shot; It features single-key marking of targets, in order of 'skull', 'cross', 'circle', and so on. Works great for chain-pulling through instances.
As of v1.2, the marking sequences are user-configurable; See the "UncleMark_Manual.txt file" for instructions.