There is an interesting article by Jill Tarter and Bernard Oliver of the SETI Institute that discusses how long we would have to transmit a signal before we could expect a reply from the far side of the galaxy (assuming anyone replies at all). The time scale is about 140 000 years, minimum. To see what timescales humans are currently thinking about, the authors searched Google using the string “x year plan”, where x varied from 1 year to 100 000 years as both a number or text. They tallied the hits and graphed them. Beyond about 100 years, the hits were dominated by science fiction and religion. There were a few events that caused spikes, like Y2K at 2000 and Yukka Mountain (the proposed US nuclear waste repository) and the Clock of the Long Now at 10 000. As it turns out, environmentalists are planing in the 500 year scale, but few other areas are receiving such long term attention. The authors note that these findings do not indicate any level of proficiency or competancy in the plans, and that these are only plans posted to the web, not filed away in a drawer somewhere.
The Wildlands Project, an NGO with ~350 member nonprofit organizations, has a 1,000 plan to restore half of North and Central America to wildlands.