Mindfulness meditation is the winner for me, find it to be the easiest to start and a lifetime to master. But ultimately for me it works to calm me, relax, and I get a lot out of it. They key is the different types of meditation, are you in bed wanting to relax your muscles and get into an excellent sleep? Is it the end of the day and you need to meditate to clear your mind and relax, the link below covers the key stuff you want to practice and become comfortable with.
http://marc.ucla.edu/body.cfm?id=22