Yes, you only need

MajorTollemache-TollemachedeOrellana-Plantagenet-Tollemache-Tollemache to be an email user there and your really going to be annoyed. :-)
(http://www.retacky.com/facts.htm)

>>llanfairpwllgwyngyllgogerychwyrndrobwlllandysiliogogogoch.com
>
>Good grief. I would hate to see someone beat this. In theory then, an email address could be something like:
>
>username@llanfairpwllgwyngyllgogerychwyrndrobwlllandysiliogogogoch.com