I'm not even interested in being revived from a coma after several years, using only contemporary technology.

Me neither. I would like to write a clause that I am awoken only if a living relative feels like they need me. This may seem like a cheat, because it's very unlikely that a child or a grandchild won't want to revive me, but the truth is, I would be content to leave it in their hands. There is no value to my life beyond my immediate network of connections. If I am awoken in 200 years to a world that doesn't know me, I might as well be someone else, and I don't mind being someone else. There's no difference between my experience of 'I' and the one that will develop in some number of years in a newly born baby.