i kicked a keg tonight. I think the last few beers were a bit foamier. Instead of the dense, small bubbles in the head of earlier pours, the head was more frothy. I also noticed this on a commercial keg that kicked a week or so ago. I had speculated that I was somehow picking up an excess of co2-- i.e., I was getting a mix of beer and co2. Again, this wasn't just the last beer. It was the last few beers.