It doesn't sound like much fun but it's actually pretty addicting :P You're living out life on a farm and you have to raise lifestock, grow vegetables, become friends with the villagers, etc for different reasons depending on the game (restoring your grandfathers farm, saving the village, etc). You can also get married, have a kid, upgrade your farm, etc.
My first HM game was Back to Nature (on the ps1) but I've played a lot more since then. So far I've played/own; Back to Nature, HM64, Friends of Mineral Town, Tree of Tranquility, and A Wonderful Life.
Has anyone else played HM? Thoughts?