Yet another option is to fly to either coast and then do runs to Asia or Europe.

If you have a fare that allows unlimited transfers, typically a EURope fare, then you can fly ORD-Europe in the evening and spend the entire day doing AUS-DFW-LIT-STL-MSN-ORD. The schedule last summer actually allowed this, and I planned it but didn't use it. If you want more info on how to bounce up and down on segment runs, seek some of tvl4free's older posts.