Nigerian scams are similar to Spanish Prisoner scams.
More Spanish Prisoner:
Incidentally, here is why that movie, The Spanish Prisoner, is called…the Spanish Prisoner (from the Urban Legend Reference Page):
The Nigerian Scam has been emptying the pockets of victims for decades — first through letters, then with faxes, and now via e-mail. In its earliest incarnation — which dates to the 1920s — it was known as “The Spanish Prisoner” con. In that long-ago version, businessmen were contacted by someone trying to smuggle the scion of a wealthy family out of a prison in Spain. But of course the wealthy family would shower with riches those who helped secure the release of the boy. Those who were suckered into this paid for one failed rescue attempt after another, with the fictitious prisoner continuing to languish in his non-existent dungeon, always just one more bribe, one more scheme, one more try, away from being released.