Wirelessly posted (BlackBerry: BlackBerry8530/5.0.0.601 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/417)
When there were still paper tickets in use, I once missed my train out of BOS. Rather than pay to buy a new ticket on the next train, I got myself to BBY station (where there are no platform guards), and when the next southbound Amtrak train arrived, I asked a conductor (on the platform) if he would honor my ticket on his train. He let me board.
Don't know if this would work now with E-tickets.