This Consumer Reports Adwatch video talks about a drug that treats Restless Leg Syndrome. The interesting bit: "…the drugs have serious side effects - one of the more bizarre involves a propensity for uncontrolled sexual or gambling impulses…"
If you watch the video (it's good, but campy -- I love Consumer Reports!), they say that in Mayo Clinic trials with the drug, there a strong tie to compulsive gambling and this drug. Two of the test subjects -- not gamblers at all before taking the drug -- both proceeded to gamble away $100,000 each while taking the drug.
Now, the test will be to figure out how to make a fine powder out of this drug and give it to the other players at your table.