What 'free' foods can you fill up on?

Here's my problem -- I usually eat healthy but when it's bedtime and it's 6 hours since my last meal, I feel hungry and it's awfully hard to sleep with my stomachs grumbling. But late-night eating will not only mess up your sleep, it's also a common time to over-indulge. So what 'free' (meaning calorie-free) foods can I use to quench my hunger?

eDiets recommends a bunch of stuff like sugar-free gelatin, chewing gum, club soda with a twist of lemon and salad without dressing. They also recommend spacing out your meals so you don't end up ravenous when you go to bed. Of course, if you're not too concerned with calories, you can have something like fruit, frozen yogurt, graham wafers or even a glass of milk before bed. Just make sure you don't eat eat something light and you don't over-indulge.