The 90-Minute Plywood Cart (that costs only $70) 

*PLANS*
measuretwicepl...
I was in desperate need of a plywood cart--just ask my wife about the heap of scrap wood in our garage! I wanted something super simple, cheap, and very fast to build.
This car accomplishes all of those objectives! The wood itself costs about $50 and the wheels were another $20. Many of you might have the plywood in your scrap pile (like I did) which means that you'll only need to drop $20 on some 2x4 lumber!
The entire build took me an hour and a half. Not bad for a project. The plans for this are essential to building the project quickly and are available at measuretwiceplans.com. They even come with a shopping list and how to optimize wood usage for minimal waste.