I might could have done so-and-so.

source: 
LAGS
Entry: 
448
Example: 
I might could have done so-and-so.
Modal 1: 
might
Modal 2: 
could
Gender: 
Female
Race/Ethnicity: 
Black
Age: 
66
Level of Education: 
Graduate school (Master's degree)
Home Community, Town, or State: 
MS (Jackson)
Location Collected: 
MS (Jackson)
Year: 
1972
Relation to Addressee: 
subject to fieldworker
Medium: 
Spoken
Sentence Structure: 
1.0
Status: 
Naturalistic