This guy sells a book for six bucks that will show you how to train your fish to perform amazing tricks, such as playing soccer (click for video). I'm thinking, we 1) buy the book, 2) train The Girl's monstrous gold fish to recover gems from flooded jewelry stores, 3) sit back and wait for a city to flood.
Doesn't the mississippi river flood just about every year? The damn fish is probably big enough to carry a pound or two of diamonds. I figure two, maybe three heists, and The Wife and I can retire! (Thanks to Megan for this link!)