So I started on this bit last week, but never got around to posting about it.
I figured that some skirts with integrated wheel spoiler-type-things would be a good next step.
Lucky for me, Honda already put some lovely side-skirts on my car about 13 years ago!
Now, unfortunately they're not exactly doing me any aerodynamic favors in their current configuration. Nothing a heat gun can't fix though.
Simply remove the fasteners from the bottom, heat and bend.