It took me a lot of energy to find the tools I needed to get started on my hardware project. So I wish to share some baseline tools for people developing hardware.
I spent the last 3yrs developing a home utilities controller. My background is Control Engineering so having done a lot of work with industrial control systems, my biggest challenge was building a consumer based unit which could go into every home in the world, which implies a $5-10 cost.
To push my projects, I ended up relying on arduino.
For other hardware projects, here is a wiki page you can source from;
This video throws more light on the arduino project
And this other guy did a good job breaking it down in terms of components.
I am interested in developments done with other open source hardware projects.
While I feel good with my software design engineering work with Quick Airtime , it is nothing compared to holding a production unit device you have engineered.
For me, it felt better than my first official somersault.
Will be happy to learn from other Hardware development teams (Asides Drone Developments 
).