Pickup Truck owners have been adding slide-in campers for many years.  There have been commercially built units for many years.  It is also possible to build one yourself.  The tools are widely available, the techniques are easy to learn, and the designs are up to you.

This video gives you a look at how I built my lightweight truck camper. The camper was built with everyday tools most people have. It is a one piece fiberglass unit. The camper weighs 630lbs dry and approximately 900lbs loaded. This camper was made to fit my 2004 Dodge Dakota. Every part of the camper was custom made except the windows and rear door which were taken from an older aluminum camper.

From Tool Man Taylor