The brother of one our customer's does his vacationing via bumps. (By the way, I can't vouch for the authenticity of this - I'm just going by what he claims).
He buys 2 seats on 3 different RDU-LAX for Thanksgiving Eve (all on different airlines). On Thanksgiving Eve, he volunteers again and again. Sometimes the timing is tough, so his wife volunteers at one gate while he volunteers at another.
Their best was 12 vouchers, a bunch of cash, plus FC trip to LAX.
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"I will not be pushed, filed, stamped, indexed, briefed, debriefed or numbered. My life is my own."