Here's an idea..... insure the guitar for ten times it's value- Then put a bumper sticker on the case that says "BAGGAGE HANDLERS ARE LOW LIFE MINIMUM WAGE MAGGOTS"
Then collect the $$$$$
No but seriously, the overhead bin is what I use. They never promise this-(that way they can discriminate if I looked Middle Eastern, which I don't)but I always end up putting my guitar anywhere I want.

P.S. If your guitar is shaped like Bloody Axe (like GENE SIMMON'S) I would'nt try it.