Had one about 10 years ago where a customer wanted to buy $2000 worth of posters and would pay us $500 for an "american cell phone" if we would ship to Africa.... never did figure out the scam, but it was interesting! Given the time frame, they were probably just trying to figure out the scam! Sort of an early Beta scam.
This is great. I got this one all the time at my last job. It was even worse when they started using TTY relay services to try this scam.
This happend to me. I was taken by surprise by the TTY relay, and I felt like it was a scam but I wasn't 100% sure at the time, so I asked the interpreter for the customers email address to follow up. She spelled it for me phonetically. "S as in Scam, N as in Nigeria, I as in illegal".