While looking for an ept family tree of Christian denominations (ha!) I ran into this wikipedia page which includes what </a></b></a>ewx describes as an excellent use of ASCII art.
Current Mood: impressed Entry Tags:ewx, recs
I've used similar ASCII trees to portray linguistic relationships in my own web pages (different orientation, same idea) so that they would work properly in lynx. (I won't link to them here because the pages contain my real name, but I'm sure you could find them easily if you're interested :-)
What would be really neat, although probably also very time consuming, is the same tree structure annotated with the form of various words, suffixes and whatnot in the forms they appear in in each language.