The $138 R/T fare I checked on can be taken SNA-DFW-BNA-DFW-SNA in one day with either an immediate turn around in BNA or next flight out.

If I'm not mistaken, the key to this fare is that it is vaild on Tu and We only.


AMERICAN AIRLINES
1888
SNA Santa Ana
Mar 06, 2007
08:00 AM
DFW Dallas/ Fort Worth
Mar 06, 2007
12:55 PM
738

AMERICAN AIRLINES
432
DFW Dallas/ Fort Worth
Mar 06, 2007
02:30 PM
BNA Nashville
Mar 06, 2007
04:10 PM
M80

AMERICAN AIRLINES
621
BNA Nashville
Mar 06, 2007
04:55 PM
DFW Dallas/ Fort Worth
Mar 06, 2007
07:00 PM
M80

AMERICAN AIRLINES
1601
DFW Dallas/ Fort Worth
Mar 06, 2007
09:28 PM
SNA Santa Ana
Mar 06, 2007
10:38 PM
738