Here are the top promo codes being offered by racing books like FanDuel Racing, TwinSpires and 1/ST BET for Saturday's Kentucky Derby, totaling over $1,100 in bonuses.

Gray horses: Gray horses look different, so they generate some excitement from people who might not care about a horse’s pedigree or speed rating. No gray horse has won the Kentucky Derby since 2005. There are three grays running this year: Sandman, Final Gambit, and Chunk of Gold.

While The Kentucky Derby weather might be hard to predict this week, you don't need a crystal ball to tell you that cell phone service might be shoddy on the infield or grandstand at Churchill Downs.