Coolness. I have the photo-resistor soldered in and your code installed. Things seem to be working as advertised.
I used a 1K ohm resistor, rather than the original spec 10K ohm (following the thread here: http://forums.adafruit.com/viewtopic.php?f=41&t=12932
to the second or third page). I see where you're munging the brightness in the interrupt handler for SIG_ADC and that you have the values for PHOTOCELL_DARK and PHOTOCELL_LIGHT set to 1010 and 100 respectively.
My question is, are these values calibrated for the 1K ohm resistor or the 10K ohm? I can go back through the various source code packages that have been posted and compare values, but I thought I'd ask first.
Have you done anything with ifdef statements around the GPS code? It's great stuff, but I'd like to dike it out of the menu at least. The clock is a gift, and I'd like to simplify the interface.
Thanks again for the code.