I'm working on a solar powered project (automated garden) and I have the solar bits working out fine (great in fact) with a 3.7V 2000mAh LiPo battery, a 6V 2W solar panel, a USB, DC, and & Solar LiPo, and a Mintyboost primarily from Adafruit. Trouble with it is that it seems to me that it's a bit overly expensive, particularly the charger and booster. While I'm happy to support Adafruit as I've learned quite a lot for their beginner friendly tutorials, I'm interested in producing more of them for friends who have expressed interest and I'd like to keep the cost down.
I'm still quite new to this and don't YET possess the knowledge to design something like this from the ground up, though I'm capable enough at following schematics.
I found from another post on this forum a 5V boost regulator for what I think is a pretty good price, http://www.pololu.com/catalog/product/798 which looks to be a good replacement for the mintyboost but I'm not sure what to do as a replacement for the charger.
I've also found through my rudimentary and most likely incorrect math that the project could probably continue to run just fine on a smaller mAh battery and panel so that should help but I'll do some more load testing on my current configuration before deciding on that bit.