IDK, I guess taking off in a VW Beetle with 3 friends from New Orleans to the Atlanta Pop Festival, with no tickets, just went. Then from their drove the bug across the country to San Francisco, with no idea what I would do there might be considered crazy. But somehow did not seem that way when I was 25.
Arranging a flight from NY to Luxembourg, then treking overland to India with no actual plan or itenerary (Slept on a park bench, stranded in Tehran) could seem crazy now, but at the time seemed perfectly ... adventurous.