Hey, I don't travel very much, maybe someone here know...
If I show up to the airport early for a flight to Chicago, can I fly standby with my ticket for a later flight?
Which airline?
American
Yes. From their website...You can now get a confirmed seat for same-day flight changes for domestic travel† on all fares for a $25 fee*. Passengers can call Reservations or handle the transaction at the airport ticket counter or Self-Service Check-In machines. If eligible seats are available within 12 hours of departure of alternate flights for your same itinerary, your flight change can be confirmed. Also, American continues to offer the same-day option of standing by for an earlier or later domestic flight for eligible fares at no charge.
The asterisks, crosses, etc basically just say pending availability.
ETA: When Tiger Fan bails on you, please remember this service I have performed.