nice project.
Just like my first try with the arduino.
Have build a Clock with an Speakjet so it can say the time. (that was not so easy even with the phrase o matic tool because this is only giving english words and my clock should speak German)
an external temperature sensor that sends the temperature to the clock over a cheap rf module every 5 minutes and goes into sleep mode for the next 5 minutes.
(made with an arduino pro mini) just testing the time it can survive with one battery charge.
only bad thing i burned my RTC and they are not cheap enough that i want to burn some more ;), so i dont have any battery backup of the clock at the moment.
i was in need to make the full clockwork with arduino code. (not so heavy with the help of the nice working time and alarm library)
but i am happy that it works now, even with some of its flaws.
i know i have done it mostly myself (of course with a lot of help from some tutorials and forum posts etc.)
thank you for all this nice developement tools and help.