When I don't move in order to remember the dream I just had, I always have this feeling - the dream is some sort of an object and I'm chasing it - I try to grab its tale, but it's like dream chase - I can never catch it X)
The greatest thing is when during the day something remind you of something in the dream. In the most of the times for me it's people mentioning something random and I can instantly recall the whole dream at once. The problem is - how to get people say the right things