After a few hours browsing the net looking for ideas on a do-it-yourslef solar swimming pool heater, I found different do-it-yourself projects that looked interesting (not swimming pool).  A word of warning though, if you are like me, you can spend hours browsing around these sites just thinking what you will build next :)

This site has all kinds of energy related from making biodiesel to “solar death rays“ (okay, solar high heat cookers) to energy producing water wheels to build your own fuel cells:

http://www.discoversolarenergy.com/resources/DIY.htm

Also stumbled across a site showing how to build an inexpensive light box for photograpy (such as items for ebay):

http://www.pbase.com/wlhuber/light_box_light_tent

http://www.instructables.com/ex/i/BEFDA1F002CB102985CB001143E7E506/?ALLSTEPS

The following site lists different do-it-yourself projects such as potato cannons,  LED light sabers, attic hotwater heater, make a robot from an old computer mouse, and much more (the photo light box links derived from this cool site):

http://www.makezine.com/blog/archive/instructables/