iam_peter,
Glad the discussion helped lead to something useful. I have often found discussions like this lead to helpful things when sometimes all that is needed is the right term to search for. In my case, I was recently looking for a way to put a 2.1mm jack on the sidewall of a box to bring in power, I was describing this to someone and they mentioned "panel mount" and voila, that's the search term I needed!
Re: the example you found & its discussion of not stealing the chip from an Arduino board to make it: I bought a couple of programmed 28-pin dip ATMega328Ps after I damaged my first one with overloaded outputs, and before I came across the method to program blank ones via "bit banging" that I found in the forum as well. So I bought a couple of blank ones too.
But instead of using them in a project, I have been using MiniPros for my fencing related projects, kinda convenient having everything ready to go without having to re-build the wheel everytime, lets me concentrate on my hardware design and coding. Have been buying from gravitech.us, and Tony there has been helpful in finding wirewrap socket strips & interconnects for mounting them in a removable method and some other parts they carry but are not on website yet.
AWOL,
"tank dive", are you referring to SCUBA? I've never tried more than snorkeling with disposable underwater cameras. Never looked into SCUBA, have enough expensive hobbies already.
The other nice thing with regular alkaline batteries is that they recover some when not being used. I wonder if that happens with low level drain also.
Robert