Once you've whetted your appetite for open tuning experimentation, your acoustic guitar having long forgotten the vanilla pleasures of EADGBE, maybe it's time to try open Aadd9 (EAC#EBE).

I would guess that nearly everyone is familiar with how a guitar works, even if they don't know the traditional string arrangement of EADGBE. Once you know that, stringing it up and tuning it is easy.