Monmouth Park in New Jersey will be offering fixed odds wagering on horses when they open at the end of the month. That means you can bet a horse at the odds at the time of the wager rather than watch its odds drop to your dismay.
A couple of things:
1. The Sport of Kings in Las Vegas got murdered offering fixed odds years ago.
2. Easy to manipulate. Make a huge bet on #1 in the regular pari-mutuel pool to get the odds up on all the other horses. Bet the horses you like at the arbitrarily high odds. Then cancel the original large bet.
I won't name names but it can and has been done before.
I wish I could go to New Jersey for the summer.
I should add that I haven't read the rules and they may have separate odds for the fixed odds wagers that wouldn't be affected by the above. Now I have homework to do.