Arduino's own website has all the introduction and specifications for its products.
I have a few little things that I want to make.
1. A small gauge display that reads sensor inputs. I want this to be very similar as Innovative Dual Gauge(oil temp and oil pressure). That product sucks. I had one, which failed a little after one year. It's just out of warranty. Thus, I bought a AEM oil temp sensor and a AEM oil pressure sensor for this project. AEM also provides specs on these sensors. I am going to wire both of them into one display and mount it on my 2017 Subaru WRX STI. Possible construction can be a hollow wood block with a 2 line LCD screen, connected to a sensor input wire and a power wire, glued on the dash of the Subaru.
2. A motorized time-lapse device. Due to many difficulties of construction and design, I was not be able to do this, although I had this in my mind for a long time. Design A. pan and tilt device. Because of the weight of the camera, a gear mechanism needs to be used. It also needs precise control, which means a high current stepper motor or possible DC motor. It will make this device rather energy hungry. Design B. Motorized slider consists of belt and gear. Design C. Pan and tilt and slider. Here is a price tag for such commercial available device. $1829 Ultimate Slider Bundle from Rhino Camera Gear. I do think that this project will take a bit of time. It makes me feel better that many people are already trying to do it. And they posted it online.
3. A CAN bus reader for AEM infinity on my Honda S2000. This is a fun project as I already have two CAN bus gauges on my car. I want Arduino to be able to read CAN bus signal from Infinity ECU and translate it. It then can be displayed on a 7 inch screen mounted on the dash, or transmitted to a raspberry pi, then broadcast into an android app. In the future, I want it to read my Subaru as well, like a little scan tool.