As Twitter has evolved from a quirky Web fad into an actually accepted and ingrained mode of communication, folks have been steadily creating ingenious new functions for the service. …. Got a "hot stock tip" via e-mail? It's probably a "
pump and dump" scheme. The sender already owns shares – and when you and others act on the "tip," the stock price soars and he sells fast – leaving you with virtually worthless shares. Ways to Spot E-mail Scams …

Switched – http://www.switched.com/