We just rescued 8 guinea hen eggs from a nest that our four hens and rooster abandoned. Put them in the incubator, and presto! 8 guineakeets!
We love our guinea hens here at the farmstead. They keep the ticks down, you don't really have to give them much in the way of shelter, and they just parade around, serenading us at dawn and dusk. You get used to their sounds pretty quick. Tough birds, those guineas. Heartily recommended.