If you're familiar with roguelikes, I'd suggest Unreal World.
It's single player though. Steep learning curve.
Terraria. It's 2d, and you've got a shitty crafting system, it's combat-based.
Illarion online - A hardcore roleplaying game with H&H comparable crafting system, supposedly it's gonna get a massive update soon so it doesn't look like crap on the graphics part. Pretty epic the way it is, probably gonna quit H&H and start playing it again after the update.
Minecraft - if you're a massive faggot you'll play this pile of shit
That's all the assistance I can provide you.
Edit: Due to engrish