Present for horse enthusiast?

Hi, I am thinking ahead to Christmas and want to get something useful for my mother in law. She is 50 and has a horse. I want to get a gift but nothing tacky like a horse notepad haha. Ideally smething that can be used. I have bout 20 quid to spend on it as im putting it with other presents. Any suggestions from any horse lovers out there would be much appreciated. :)