Between the rabbits and the groundhogs my entire spring crop of lettuce, chard and spinach was eaten. I built this cage to fit on top of the raised bed that these crops grow in. The cage is made of 2X4 scraps I found in the garbage at a construction site. First I ripped them in half. Then I built two squares using butt joints. The squares are the same size as the underlying boards for the raised bed. Then I joined both squares with a length of ripped 2X4 the length of the chicken wire (1 foot). You can easily double the height. The chicken wire is stapled on using a staple gun. I also "sewed" the chicken wire segments together with baling wire and zipties.
To make it easier to access the crops I put hinges on the end. I might attach a rope to limit travel to 95 degrees. I'm planning on making a much taller pentagon with five 1 foot wide segments for beans and peas. The tomatoes are going to need a huge cage.
It's been about three weeks and you can see the seedlings popping up unmolested. In the winter I plan to cover it with plastic and convert it to a greenhouse.
UPDATE 04 OCT 2013 - I added another picture and you can see that the chard has grown well and I finally have spinach and lettuce. With the weather getting cooler, these are growing better.