Whoa… On the Dutch forum dude describes his “bubble counter” for on the air lock. Sorry, it’s in Dutch but there’s good pictures. If someone here REALLY wants to get in to this, I can help establish communication.
That’s pretty cool. 
Here is how google translate renders it. It is readable, although imperfect.
Very cool, thanks Tom. Will do that from now on.
Cool, but worthless as anything other than entertainment. ;D
I have a new tag from that though.
Measuring is knowing
Meten is weten dus.
Now there’s a neat invention.
How long before we’ll see it for sale at morebeer.com? ;D
Jazeker.
That’s a beer geek, for sure. (I mean that in a good way though ;D ).
Pretty awesome thing. Actually, I would think looking at the data curves would be kind of interesting.
Search the HBD for a guy named Fredrik. Swedish guy with a bubble counter a few years back.