Hi Cheater,
I can't believe you're in Brisbane! Small world huh?
The voltage booster sounds like an interesting idea. Would there still be a potential problem with the max. current of the large capacity lithium batteries, as they're only rated to 200mA continuous (some only 100mA) and 400mA pulse? Given that the GPS logger is supposedly using 160mA when active, I guess it shouldn't be a problem for 200mA+ batteries. Would the Maxim chips be much of drain on batteries? We've also been messing around with some mini solar panels (http://www.powerfilmsolar.com/products/oem_components/modspecs/sp337.htm) in the hope of trickle charging collar batteries and these chips might be perfect for boosting voltage.
Another question I have in relation to GPS and the Arduino boards is whether it might be possible to set up something to trigger a small wireless camera on a collar when a collared animal gets close to waypoints? We tested a prototype wireless camera collar last year with great success, and since then I've been looking to develop the camera collar idea further. I've been interested in GPS controlled devices on-board collars for ages, but my lack of electronics knowledge has left me day dreaming about such ideas.
I am due for some fieldwork within the next couple of weeks, which will see me away for about six weeks, but if you were keen, it'd be great to follow up on some of these ideas upon my return.
Cheers