Mary Cooper: Well, I would have to say when he was thirteen and he tried to build a nuclear reaction in the tool shed.
Sheldon: Ooh, this is a good one.
Mary Cooper: Now, the first thing you need to know about Shelly is, ever since he was a little boy, he was always concerned with the well-being of others. And he didn't think it was fair for people to pay for electricity, so he was gonna power the entire town for free.
Sheldon: Tell her about the uranium. Tell her about the uranium!
Mary Cooper: Oh, well! Well, this is adorable. When he arranged to get some yellow-cake from Chad, I thought he was talking about twinkies from one of his friends.
Sheldon: Yeah. But I wasn't, because I didn't have any friends.
Mary Cooper: No. It turns out this little scallywag was trying to use my Visa card to buy uranium from an African warlord in the country of Chad.