CAGED: a useful way to learn guitar chords without having to buy and memorize huge books like 1001 Guitar Chords. The idea is, there are only five chord forms in the open position; any chord type can be played as a C, A, G, E, or D chord. Once you've memorized how to play a chord type in all five of these forms, you can transpose it up the neck to any position and any key you like.

For example, the F#maj7 chord cannot be played in open position. So, to figure out the best way to play it, we first look at the five CAGED forms of the major seventh chord (in tablature form, of course):

-0--0--2--0--2--
-0--2--0--0--2--
-0--1--0--1--2--
-2--2--0--1--0--
-3--0--2--2-----
-------3--0-----
 C  A  G  E  D
We can now transpose each of these shapes up the appropriate number of steps, to achieve five different forms of the F#maj7 chord.
-6--9--13-2--6--
-6--11-11-2--6--
-6--10-11-3--6--
-8--11-11-3--4--
-9--9--13-4-----
-------14-2-----
 C  A  G  E  D 
Of course, some of the forms you come up like this with may be a pain in the ass to play, so you can often abbreviate them by not playing certain strings; just make sure you include all the important tones that make the chord what it is (I'd want to keep the tonic note, the third and the seventh in the case of a seventh chord without an altered fifth). In a pinch, I'd play each of the above chords as follows:
-6-----13----6--
-6--11-11----6--
-6--10-11-3--6--
-8-----11-3--4--
-9--9-----------
----------2-----
 C  A  G  E  D 
If you sit down and work on your CAGED chord forms for a couple hours a day, first learning the triads and seventh chords, then moving on to added tones, you'll be able to comp with the best of them in no time. If I'd known about this last year, I wouldn't have gotten such an ass-beating on the jazz band try-outs.

As a side note, the CAGED method not only makes the Everything Guide to Guitar Chords completely obsolete, but is also much more useful for aspiring guitarists, as it actually teaches some technique, and is helpful in learning the patterns and shapes on the fretboard. As far as I'm concerned, the EGGC is mainly a scheme invented by NFNers.