In DF, workshops are buildings where crafting can be done, then there are rooms which are an area containing items, I was thinking everything could be done in terms of rooms, including workshops, if you wanted a metalsmith's forge, it would be a room with a forge, table and anvil in it.
So, I've started working of this DF clone, so far I've got a region generated, dwarfs running about with A* path planning, simple designations(mine, channel, chop tree, build wall and build ramp) simple building of workshops, a few items that can be made at said workshops, stockpiles and multiplayer over tcp/ip.