Besides the Cullen DNA Project, I'm also interested in my Y-chromosome haplogroup, which is a way of placing people into the grand family tree of all humanity. I drew up this tree to explain some of the new research on haplogroup I2a, and I'm placing it here so other people can easily see it. This tree is based on Ken Nordtvedt's Warped Founder tree at http://knordtvedt.home.bresnan.net/WarpedFounderTree.ppt
My cousin in Ireland and I belong to I2a1-"Sardinian" which gets its name from the Italian island of Sardinia where it is most common (this is just a convenient label--our ancestors probably never lived in Sardinia--some distant "cousins" probably were among the first settlers of Sardinia thousands of years ago).
No other Cullens are known to belong to any other group of I2a, all other Cullens tested so far are either R1b, I1, I2b1, or I2b2.