How can I make my sit ups more interesting?

I was doing them again faithfully for about two months. Got up to about 60 a day. Then I quit because they’re SO BORING and I didn’t think they were doing that much for me. Well, the last couple of days I’m going, “Uh oh. You know what? They WERE working.” I need to start doing them again but I need some sort of something else to think about or do at the same time…..