1. It needs to use as little power as possible because it's solar powered (with some battery for winter and night time)
2. It needs an RTC that updates using GPS (every day or so)
I have not found a way for the mp3 player shield to use less power or be turned off yet (any ideas?).
This is a large project and the needed features might eat up to much of the ROM. One idea here is to use 2 arduinos.
I was thinking about wave shield also, but i will have a very large selection of files. meny houres of content if possible. But i will get a shield and see what i can get out of it.