[anghyflawn]

Wait, what? Are you saying barcodes aren't used in the US? Here in Norway at least all major handling agents issue boarding passes with barcodes, so you can board a (domestic or intra-Scandinavian) flight without interacting with anybody human except the security agents just by scanning the barcode at the gate. No idea if it's also used for security purposes, though.

[mahyarm]

The ticket has a barcode, but it's usually scanned by the airline before you board the plane. The TSA checker just looks at your ticket and your id, no computers involved.

[FaceKicker]

And presumably the passenger's name is encoded in the barcode, which I guess is why the OP suggests printing the original ticket with the name of the friend that bought it instead of just using the "forged" ticket at the gate. Though I'd also guess that the airline employees who scan the ticket at the gate almost never check that the name on the ticket matches the one displayed on their screen when they scan the barcode, so you'd probably be fine using the forged one.

[mahyarm]

This wouldn't work for international flights, since they often check your passport before boarding.