Homemade Sausage Making

I had some double smoked sausage from a shop in Edmonton, which was quite good and buddy mentioned that in Langley BC, he had sampled some and commented that it was also quite tasty. I've never done and honestly don't really know the process. Didn't really see anything on the site nor on the web either.
So the question is, has anyone done a double smoke sausage / bacon? Is it a temperature thing, duration, different types of woods, etc? Would someone be willing to shed some light on the methodology.

You didn't read my last post about my venison sausage. Numerous Polish sausages are double smoked. Look at myśliwska, krakowska sucha. Usually done with sausages that are poached after the first smoke. Sausage is smoked with warm smoke on the second day for 2-3 hours, then rested without cooling with water. Some smoke a third or fourth time. This will give the sausage a stronger smoke flavour, drier texture and darker skin. Bacon can be smoked for a number of succesive days if cold smoking.