Terasology is an open source game that "pays ample tribute to Minecraft in initial look and origin" but is eventually going for a caretaker style of gameplay a la DF and Dungeon Keeper.
There's not much gameplay at the moment, but basic mining and crafting is in as are abandoned villages.
There is no 3x3 grid as in most games that look like Minecraft (Minetest or its Voxelands fork if you want a few others that I was considering). You open your crafting menu and all of the things that you can make are displayed. You also can't gather wood until you make your first hammer-axe from twigs (break leaves), stones (dig dirt and you might find one), and sticks (break branches). I haven't played much, but the crafting seems more interesting to me. It's almost like an easier start for TerraFirmaCraft, if you've played that.
It seems to be wide open to modding, sporting a module system and coming with ~30 (sorry, I didn't count while at home and am now at work) prepackaged modules. A few current modules include the aforementioned villages, computers, a hunger system (though I haven't found any food yet), more ore types, and seasons.
Sorry if you're experiencing an overload of voxel games. I've been looking for a project to hack on for a while now and this is just far enough along that I'm interested in becoming a contributor but not so far along as to be daunting.