TTL Serial JPEG Camera with NTSC Video can be a pretty neat project addition. It was designed to be used in security systems and does two main things - it outputs NTSC monochrome video and can take snapshots of that video (in color) and transmit them over the TTL serial link. You can snap pictures at 640x480, 320x240 or 160x120 and they're pre-compressed JPEG images which makes them nice and small and easy to store on an SD card. Perfect for a data-logging, security, or photography project.
One nice thing about TTL Serial JPEG Camera with NTSC Video is all the 'extras' that come with it. For example it has manually adjustable focus, auto-white-balance, auto-brightness and auto-contrast taken care of for you as well as motion detection built in. That means you can have it alert your project when something moved in the frame.
Using TTL Serial JPEG Camera with NTSC Video is pretty easy and only requires two digital pins (or a TTL serial port) - by default it transmits at 38400 baud. There is also an Arduino library developed by Adafruit which has example code that shows how to change the image size and compression quality, detect motion, control the video output stream
Note: TTL Serial JPEG Camera with NTSC Video works great with classic Arduino UNOs (and other Atmega328-based microcontroller boards) but they are not yet MEGA compatible.
Arduino library developed by Adafruit
DSP management tool (Windows only)
Protocol Cheat Sheet for the sensor
Adafruit Web Site: http://www.adafruit.com/products/397