Here is a jam track made with a part of the tripfuse25 idea above.

Improvising Two Chord Jams

This chord progression is actually C#m to A however what is fun about that is when you play the Emaj7th arpeggio over the C#m we end up hearing and C#m9 sound.  The B in the Emaj7th chord makes the C#m7 and then the D# in the Emaj7th chord makes the C#m7 turn into C#m9..

C#m:  C#  E  G#

Emaj7th:  E  G#  B  D#

C#m7:  C#  E  G#  B

C#m9:  C#  E  G#  B  D#