I learned a new primary technique for me anyways. I was at my lhbs and i noticed that they had there airlocks on the edge of the bucket lid rather than the centre, they told me they ferment with the buckets on a bit of an angle to create more headspace for karuasen (sp) not by volume but by distance. I tried it with my latest brew and it was the first non blow off tube ferment which didnt come out the airlock.