In the better late than never camp, I just finished off the new cold frame (an unheated green house). This is a project that started this summer, and I needed to finish it before first snow so that we can get the cars back in the garage.
Made of 2" Ceder and Thermoclear sheets (which is corrugated Lexan with a UV coat), it should hold up for quite a while.
All the joints were done with a Kreg Jig, a completely invaluable tool that I got to know during the day of service at the Poughkeepsie Farm Project a few years ago.