I accidentally traveled without ID last year. My drivers license is the only picture ID I carry. I'd given it over to test drive a baby seat at a store, and forgot to get it back. Left for vacation the next day.
My stops were Portland, San Jose, and Austin. At all three airports I explained my situation, showed them my YMCA card (or library or credit card or something) and they marked my boarding pass for special security. The processes were not draconian, just a pat down, and actually faster than the regular security line. I skipped the line and went to some designated place on the side, zipped through the pat down, and then had to wait for my properly ID'd wife every time.
YMMV, but based on my experience, I highly recommend traveling without an ID!