Ours is the ZooMed Repti-Fogger...
It is very good although I don't think it was very cheap (I think about £60 if my memory is correct) We have had it for a few years now and it has never failed us yet
If your on a budget the dripper systems are very easy and cheap to make...depends what kids of effect you are after really...what setup is it going in to? you need to make sure it is very waterproof, it does get it very wet! which is why we only have it on for fifteen minutes a few times a day...!!!