I like that, Mr Red. Here's some "replacement thoughts" (affirmations) that work well for me. When I have trouble falling asleep its usually because I'm worried or overly stressed. So I just pick (or create) one and repeat it over and over to myself. This silences the stressful thoughts and creates a feeling of calm and comfort instead, which I enjoy until the (eventually very boring!) repetition drives me straight to lah-lah land ...

"I now give my mind a joyful vacation."   

"I now release the events of the day and drop off into a deep peaceful sleep. I will wake up in the morning refreshed and revitalized and looking forward to another wonderful day!"

"I love life, and tomorrow always looks after itself. All is well!"

(affirmations paraphrased from Louise Hay's "You Can Heal Your Life")