You might consider a wall mounted gas stove. They come in all sizes and styles. Some are very pretty. I think some are designed to work with either natural or propane gas.

In any case, don't buy a unit unless you have actually seen it lit up.

A bit late to chime in but you should check out lagunawaterworks.com. I don't know if you have thought or heard of biofuel fireplaces. I purchased one for the house we recently sold(building now). They offer floor and wall mount. They are really cool I think and you don't have to run a gas or electric for them.(The issue with our old house) You can also purchase the biofuel from them. My double sided(see through) would burn for about 3 hours on about 16oz of fuel. Hope this helps.