Be aware that a foot soaking machine might now be a bit of a clichéd present. I bought one for my mother a while ago and I don't know if she's used it more than once (although it was bought with the best intentions). Recently she was given another one by a friend, and another one of her kids gave her yet another one.
I'm not sure if it's just that people think she is on her feet too much, or if it is the gift to give at the moment, but you might want to check before giving this present to someone. They might already have one!