Throwing this out there to see if there's any interest- I'm planning on doing the "Great Mississippi River Tour" in my little Mooney. Should be roughly 1300-1400 miles of flying, and about ten to fifteen hours of flight time.
The goal is to go VFR from the very headwaters of the Mighty Mississipp' down to the Gulf. The first leg will begin at KPKD Park Rapids, where Lake Itasca is just a few minutes north, and marks the official start of the River. From there up over Bemidji, down over Grand Rapids (MN), Brainerd, Little Falls, St Cloud, through the Class Bravo at KMSP, and then along the widening stream the rest of the way.
Tentative stops are all right along the shores, but include La Crosse, Moline, Saint Louis (barbeque and blues), Cairo, Tunica (gambling!), and the Big Easy (general debauchery).
Goal is to finish in the next three weeks, as my schedule gets busy again at that point, and I'll have less daylight available for VFR. In any case, if anyone would like to join reply or email me b o a s t l e r [ a t ] g m a i l [ d o t ] c o m (no spaces, obviously) and let's take a trip.
EDIT: I am in NY, so I was planning on the flights being in the early evening EDT, though I have some flexibility, and some availability on weekends.