I'm getting close to finishing my winter-themed Realm of Battle board (Will have pics of the finished product soon, watch the Terrain board for them!) and basically right now, I want terrain. I picked up some trees at my FLGS and I have my Aegis Line, but I definitely need a few more things to plonk down on the table and give it a "lived in" feel.
There will probably be a Bastion and Wall of Martyrs in the future, probably some more trees too.