I use a "sleep machine" when I stay at my condo during the work week because of noisy neighbors. The type I use is just a "rushing air" type, has several speeds and also adjustable louvers and vents to change the volume and pitch of the air sound. It's made by Sleep Mate, only about $29, and has served me well. They make other electronic models with synthesized cricket chirps, water falls, rain, etc., but I found them distracting. The rushing air is the most soothing, and would be similar to what many of you hear from your fans. I think it's better though because you don't create any drafts like you do with fans. Sleeping in a draft always gives me a stuffed up head.
Viper: That IS your pulse you are hearing.