Generally religious and historical correlations, and also linguistic roots. I am rarely certain of the accuracy of my sources though.....just the occasional thing I read around and suchlike. I don't really know anyone who is both interested and a reliable source/confirmation with things like this.
Also, the changes that were made in translations of religious texts I find quite interesting..i don't know why...I can't read hebrew but i have read small bits of the anglo-saxon bible, and the differences with the king james are quite odd at times......
~netweaver~