That's what these letters I keep getting are promising!

For some reason, I keep getting these pyramid scheme letters in the mail from people I have never heard of, all over the US.  I have no idea where they are getting my name and address.  Silly me, I thought that those things were illegal (not to mention that they don't actually work...). But all I have to invest is about $150 or so for materials, and I will make $250,000 in only 90days! Anyone want to be rich with me?