As you may know the new X++ editor in AX 2012, is actually the Visual Studio editor.
One of the sweet things that gives us, is the ability to do "Find as you type" searches in the code.
Press CTRL + I once, and set of binoculars pops up. Now start typing, and you can see how the editor starts to find matching values in your code. If you want to stop the typing, and just find the next instance of the same text, just press CTRL + I again.
To search upwards in the code, press CTRL + Shift + I.