DS is 3 in July and decided to go without the dummy about 2 months ago. I put him to bed for his day sleep, and could'nt find any of his dummies. I told him I'd go and find one and that he should just close his eyes while I was looking. I heard no noise from the room so refused to go back in. He slept for 2 hours no dummy and didn't even ask for it afterwards. He's not had once since.
He will sometimes see DD's (if we are at the IL's and they have allowed DD to bring it out with her... she doesn't have it except for bed 99.99% of the time), and he'll take it away from her tell her dummy's are yucky and only for sleep, and then he'll go and chuck it back in her cot.
It has been SUPER easy and I'm really glad I waited until DS was ready to get rid of it. Completely stress free.

We made sure from 12 months of age that his dummy was only ever for sleeping and it would only ever be allowed on his bed during the day. He never brought it out although did ask fr it. We just ignored him.