I have very little experience with the Arduino and am hoping that you may provide me with some helpful info.
I would like to build a device that records time spent on a project. I envision the main Uno with a switch, microSD breakout, and an LED to indicate its tracking your time. When setup the user could simply press the switch/button (light up the LED to show you're "working") and while you plug away on your day job the Uno will track the time between switch on and switch off. Then at the time the switch is turned off, have the Uno write a simple data file containing the total time spent on that activity.
I have a basic idea of what I need hardware wise, but am hoping to find insight to the backbone of software programming to make something like this begin to take shape.