The Grand Rapids Riddler - a free annual treasure hunt in the Grand Rapids, Michigan metropolitan area (in the tradition of the Wyoming Riddler, who did free treasure hunts in the same area for over 30 years). Solve the riddle and retrieve the medallion to claim the prize. The annual hunt starts on the first Tuesday of November every year.

Also look for small, free Google Maps Challenges which are fully armchair and can be solved from the comfort of your home, wherever that may be. Win at least a $25 gift card with each challenge. Check the website to see if there's an active hunt.

Bigger hunts with bigger prizes (which require a book purchase) coming again in the near future!