By distancing themselves from Earth's center of gravity, astronauts who spend 18 months in the International Space Station shorten their perception of time several ten-thousandths of a second. Effectively, they're using Einstein's theory of General Relativity to infinitesimally (but measurably) increase their own life spans.
Sometimes, because the Earth isn't perfectly spherical, but is an 'oblate spheroid,' I like to remember that I get to do the same thing pretty much any time I climb a latter or a flight of stairs or a small hill.
Granted, I lose out again every time I walk down stairs or fall into a small hole, but eventually I'm hoping that I'll accumulate enough microseconds through my temporal Office Space scheme to outlive the rest of my friends.
Also puts a new perspective on moving to Florida: it's not that old people like the climate better, it's just the closest the can get to actually living on the equator to cheat death a little longer.