Worse than useless -- net negative -- everything related to Iraq/Afghanistan. I didn't go over there because I thought it was a good idea (nation building in either place is dumb, and any conflict at all in Iraq was dumb), and while individual projects sometimes made things locally better (like, speeding up network connectivity on a specific base), it was overall a dumb project which made things worse because it was done. Got paid pretty well, met interesting people, learned a lot, did stuff I'd never have gotten a chance to do otherwise, but yeah, net-negative.