It's been blistering hot here lately (yesterday temps where up in the 120's in direct sunlight). In an effort to help keep the boat interior temps down, I rigged up a couple of tarps which nearly cover the entire deck with shade when the sun is overhead. The forward tarp is an 8x10, the after is a 10x12. It has helped a lot, even though it looks a bit odd. (Note the hanked on genny; I've been sailing 3-4 times a week, and hadn't pulled it off yet when I took the picture. I can go from liveaboard to heelable in 30 minutes, unlike all the other boats on my dock which rarely (if ever) leave.)

Whole setup:



CrewDogs diggin' the shade:



Looking forward from underneath:



And aft. I use my whisker pole to hold the corners out, providing much more shade that way: