One of the most confusing things about genealogy is when you get into those second cousin once removed situations. Nobody know how that works.
I have seen a number of nice charts, and I've added my own. This one includes a blue shading for just how much DNA you share with the person. I think this really helps show just how much you are related to everyone.
|Genealogical Relationship Tree with shared DNA cM|
I'd like to thank all the others who have done so much more work on both relationship mapping and genetics. Alice J. Ramsay created one of the first relationship charts back in 1987. And if you really want to fully understand DNA and cM sharing, you'll want to read more from Blaine T. Gettinger, The Genetic Genealogist.