A picture may be worth a thousand words, but Michael Stadther can top that: His illustrated children's book, A Treasure's Trove, could be worth just over $1 million—if you can solve the riddles. Hidden within the 116-page forest-world fantasy are clues to the location of 12 golden tokens, each of which can be redeemed for a jeweled insect brooch valued at $8,500 to $450,000. "Anyone who can read can solve the puzzle," says Stadther, 53, a lifelong treasure-hunt fan. "I've [always] wanted to do this."

Readers are glad he did. The book—self-published in November after Stadther (who sold his software company for $100 million in 1996) was rejected by a dozen publishers—has sold more than 150,000 copies, hit the New York Times children's bestseller list and was just optioned by Tom Cruise's film company.

In addition to writing and illustrating the story himself, Stadther hid the tokens with help from his wife, Helen Demetrios: Each is in a public place and, he says, there's one within a day's drive of anywhere in the continental U.S. The search "is addicting," says fan Ted Mann, 27, of Philadelphia. "I've been doing it nonstop." To date, all tokens remain hidden, and Stadther, who lives in Westchester, N.Y., won't give hints no matter how much you beg. (If you think page 77 holds a clue, though, see box at left.) His own reward: "I get e-mails from parents saying their kid hasn't watched TV all week."