I saw this design in a book ( I think 101 sailboat projects) and made them for my boat. I used a blackout cloth which does a great job of blocking the sunlight but does tend to wrinkle a bit unless stretched out along the bungee cord as can be seen from the picture. When I want them off, I just remove the bungee cord from the hooks and stow them or sometimes I fold and put the upper cord on the lower hooks.
Pat, thank you for the picture! That is a good option and one I may just try. Not so much worried about the light, as I am privacy. Might get Sunbrella cloth that will match my cushions and make the curtains out of that. Thank you!
My wife and I went to the Strictly Sail boat show in Oakland this weekend and saw Peek-a-boo port shades on some Island Packet's. They looked pretty good. I searched online and found the cost to be $300 + for an e27.
I ended up making something like the link above. The shade I bought is; http://www.bedbathandbeyond.com/product.asp?order_num=-1&SKU=14305645&RN=686&KSKU=109654 one shade did all six ports. It's a cellular shade that a 5/8" dowel fits nicely into a cell. The smaller shades are held open with Velcro and the larger shades have a Dacron loop with a button. Bungee would probably work better for the loop but I had the Dacron line handy .