One of the projects that I'm interested in building is an alarm clock with a variety of alarms to wake a person up. I've though of using LEDs to simulate sunlight, a motor to vibrate my pillow, a speaker to play music, a squirt gun, a spring-loaded mechanism to pull off my sheets, etc. I haven't built one yet, but the project has always been in the back of my head. I cam across a series of alarm clocks that simulate sunrise, and I like the one in the link below, particularly for its great bill of materials. I would use an arduino instead of the Arm processor because I have a few ATMega328p's I haven't found projects for. He also uses all open source products to create the project, which I think is awesome. I haven't dabbled in board layout much, and an open source program would be a great place for me to start.
Dangerous Prototypes has a sunrise alarm clock that uses a PIC32. I've used one for another class, but since I'm focusing on ease of teachability, for now I'm going to stick with the arduino (very beginner friendly). This one plays sounds back, which is nice, but I can do that with an arduino as well.