I've seen tons of information on the Web about pentatonic scales. Usually, they're writing/talking about major and relative minor pentatonic scales. There's another minor pentatonic scale that I don't see discussed so much: the "melodic minor pentatonic" scale. (This seems to be the most commonly used name for the scale; there are others. If I'm not using your favorite scale name for this, please don't bother writing me. You can call it "Gertrude" if that makes you feel better. Thanks in advance.)

A major pentatonic scale can be thought of as tones 1, 2, 3, 5 and 6 from the standard major scale. In C, that would be C - D - E - G - A.

A melodic minor pentatonic can be thought of as the same numbered tones from the melodic minor scale.

For C minor, those notes would be C - D - Eb - G - A.

Since this scale is just a subset of the melodic minor scale, we could use it anywhere we might use a melodic minor scale.

For example, C melodic minor pentatonic could be used over:

• Cm , Cm6 or Cm(maj7) and its extensions. Since there is no seventh in the scale, it could also be used over Cm7 and its extensions.
• F7, F9, F13 (There's no Bb or B natural in the scale, so it could be used as well over F7(b5) or F9(#11).
  
• Am7b5 (Aø)
• B7alt (There's no B in the scale, but that's an obvious note on B7 anyway.)
  
• Ebmaj7(b5)

There are other uses, but these are the "meat and potatoes" situations you'll probably run into most often.

If this whets your appetite, there's a corresponding lesson on my YouTube page... check it out.
Here's the stuff I played over the backing track near the end of the video lesson: