Building an offset smoker

[eunosben]

After researching smokers a bit I thought it would be fun to have a go at building my own smoker.
I'm thinking of having a 200ltr drum connected to a 25ltr one for the fire box by a short piece of pipe. And then a flue on the opposite side of the big drum. Does this idea sound feasable? Is there anything else I should fabricate in to aid the flow of smoke over the meat etc?