Here are a few finished products I have designed. I have shown a selection of projects that were designed completely by me through every stage of the development process.

Harddrive surge protector and power stabilizer. This filters the power supply of the computer harddrive, making it more reliable and providing dedicated surge protection. In testing the power output was seen to be 1000% cleaner.

Plant water indicator. This is an alarm which sounds when the soil is dry but only when it senses motion in the room (such as a person), which saves battery life. It also turns off automatically at night and has about 3 years battery life off a single 9V PP3 battery. All the light-related functions come from a single LDR and the moisture sensor is a metal probe that measures the resistance of the soil. It uses no integrated circuits, and draws so little power that it can be powered by a lemon battery.

Car powered adjustable voltage regulator. This can output any voltage between 1V and 12V and can be powered off a car or any 12V power supply. It is small and cheap.

Portable, waterproof, EMP-proof, drop-proof, battery powered speaker. This is compatible with mp3 players and has very nice sound quality.

Other designs include: radio transmitters, LED drivers, IR camera mod for webcam, musical synthesizer, computer parallel port interface, USB powered peripherals, etc.