Another suggestion, don't make a production out of leaving the house or going to bed; whenever you use the crate for confinement. All that "We'll be right back" stuff doesn't help them (since dog's don't truly speak English) and can often function as a "cue" for them -- in a negative way. If you've seen dogs that run and hide under the bed when their people announce their intention to leave the house, you know what I'm talking about.
I love all the ideas for making crate time, fun time. Cookies "hidden" in the bedding was always Bo's favorite. Bea preferred having a chew toy -- a large Nylabone; something VERY SAFE -- when it was time to kennel up. Now she goes to the toybox, selects a toy and takes it back to her crate for some private chew time. (Bo can't steal it, if she's in her crate, you see. Smart girl.)