Jochen Gross made this wonderful compilation of digital wood joints under CC license (various CAD files also available to download on his site).
I wanted to be able to look at them all at once at marvel at their beauty, so I whipped up this poster-format visual reference. It's under CC non-commercial share-alike license. Large .PNG here and downloadable PDF below. Enjoy!
edit: in case you don't have access to a plotter or other large-format printer, I've put it up on Society5 print-on-demand site. You can find it here.