A subject that never comes up, and something that I've been working on lately. I flogged these examples out of the The Guitar Handbook by Ralph Denyer. I find them very useful - you might too.
Code:
+ = Augmented
o = Diminished
# = sharp
b = flat
Substituting Minor 7th and Dominant 11th Chords
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Original Progression
C / / / | F / / / | G7 / / / | C / / / ||
Subsitution
C / / / | F / / / | Dm7 / G7 / | C / / / ||
C / / / | F / / / | G11 / G7 / | C / / / ||
C / C7 / | F / Dm7 / | G11 / G7 / | C / / / ||
Extending and Altering Dominant Chords
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Original Progression
C / / / | F / / / ||
Subsitution
C / C7+9 / | F7 / / / ||
C / C7b9 / | F7 / / / ||
C / C7+5 / | F9 / / / ||
Original Progression
C / / / | B / / / ||
Subsitution
C7+9 / / / | B7 / / / ||
C7b9 / / / | B9 / / / ||
C7+5 / / / | B6 / / / ||
C7b5 / / / | B6 / / / ||
Inserting New Dominant Chords
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Original Progression
G / / / | C / / / ||
Subsitution
G7 / C#9 / | C7+9 / / / ||
G7 / C#7+9 / | C7 / / / ||
Original Progression
G / / / | Gb / / / ||
Subsitution
G7 / Db7 / | Gb7 / / / ||
G7 / Db9 / | Gb6 / / / ||
Substituting Minor Passing Chords
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Original Progression
C / / / | F / / / ||
Subsitution
C / Dm / | Em / F / ||
C / Am / | Dm / F / ||
C / Am / | Em / F / ||
Substituting Diminished 7th Chords
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Original Progression
C / / / | G / / / ||
Subsitution
C / Go / | G7 / / / ||
C / Gbo / | G7 / / / ||
C / Abo / | G7 / / / ||
Original Progression
C / / / | Dm / / / | Em / / / |
Dm / G7 / | C / / / ||
Substitution
C / C#o / | Dm7 / D#o / | Em7 / Ebo / |
Dm7b5 / G7 / | C / / / ||
Original Progression
G / / / | Am / / / | Bm / / / |
Am / D7 / | G / / / ||
Substitution
G / G#o / | Am7 / A#o / | Bm7 / Bbo / |
Am / D7 / | G / / / ||
Choosing a Different Chord For Every Beat
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Original Progression
C / / / | F / / / ||
Substitution
C C6 C7 C9 | F / / / ||
C C+ C6 C7 | F / / / ||