Just finished watching my first episode of Kolchak: The Night Stalker (note, the presence of a colon in the title does not mean its a White Wolf product). I love it - which means thanks to Netflix I've had the chance to become a fan of two great old TV series, Doctor Who being the other.
So, the first episode concerned an immortal or ghostly Jack the Ripper. For fun, here's some stats for the ripper for both Swords and Wizardry and Mystery Men! ...
Hit Dice: 8 (60 hp)
Armor Class: 2 
Attack: 1 weapon (1d8+2)
Special: +1 or better weapon to hit, immunity to cold, fire and poison, double damage from electricity, magic resistance (40%), spells
The Ripper may once have been a man, but long ago he slipped into legend as an immortal spirit of murder. He appears every few years in a different city, murders five women and announces his murders with rhyming letters sent to the authorities and then disappears. The Ripper can use the spells at etherealness, haste, jump and levitate at will. The Ripper consumes the souls of the women he kills (and only women). With each soul consumed, he gains one additional Hit Dice, six additional hit points and improves his Armor Class by one. Once five souls have been consumed, he is able to teleport to another city to continue his murder spree, his statistics being set back to those presented above.