Here is an excellent link for an overview of this endlessly fascinating subject and a look at those who claim some sort of lineage.

Also included is the story of the Jewish false messiah Shabbetai Zevi and the messianic/end times fervor that swept Europe and the Middle East in 1666 because of this man. ultimately, he was brought before the Sultan of Turkey who demanded Shabbetai either prove he was the messiah on the spot, or convert to Islam (or die.) He promptly took off his Jewish garb and donned a turban.

http://www.pbs.org/wgbh/nova/israel/

Funny how that works...