"Free" blind spot detection mod 
I am not a fan of blind spot detection systems (or lane departure alert, automatic cruise control, etc.), and I would be a lot happier with the European left and right 'blind spot' convex rear view mirrors. I imagine it is one more obsolete DOT rule but that this one also makes carmakers happy: they either use a cheaper piece of mirror or they charge you $3,000 (incl. a 200% margin) for a gizmo package that includes blind spot detection.
Convex auto-dimming mirrors can be ordered online (i.e. from ECS tuning), but I found $416 -a piece- way too expensive
The Society of Automotive Engineers published a paper in 1995 explaining how outside mirrors could be adjusted to eliminate blind spots:
I follow this recommendation and have my mirrors adjusted according to Fig.1 and Fig.4. There are nevertheless instances were I like to have them in the classical Fig.2 and Fig.5 position: backing out of my garage, parking in a narrow spot etc.
Being (almost) the only driver of my F30, I am using my memory seats as a work around. I have programmed the memory settings #1 and #2 with the exact same seat position and only the position of the mirrors differ.
when I back out of my garage in the morning, I select the settings #1:
then I get on the street, press the memory button #2 and my mirror switch to the 'SAE' settings:
Nothing earthshattering or incredibly smart here, but I thought I would share just in case...