My practice routine I picked it up somewhere but I can't remember where. I think it's actually a common exercise in the "music world". Ya I look at a fret and string and know exactly what note it is without keying off the surroundings (but thats what I used to do before I did those exersices ;)).
Although sometimes it will happen that I go: whoops whats that one already ?and look at the surroundings and go : Oh ya ! But it's happening less and less.
You get to know that 3rd sting 8th fret is a D# the same way you look out the window and know that this is a tree and this is the mailbox and this is a dog because you learned it at some point in your life.
The next step after that (the one I'm working on right now) is to be able to do the same thing but without looking...by ear. You play a note/chord, or have someone play it, and name it. That's such a great tool to have for improvising/jamming with others. But that's a bit more work then a month of practice...for me atleast