Ever since I got the car, I noticed there was a rattle if I bumped against the driver side door panel. This didn't happen with the passenger side one. So I removed the door panel and as soon as I peeled the panel away at the bottom (it's attached with velcro), a nice M4 or M6 bolt dropped out. DOH! The washer was still hanging on for dear life on the velcro. A few twists of my socket driver and I'm rattle free...woo hoo! I also gummi-pflegde (sp? ...it's a BMW product) the seals so maybe the squeaks will be gone too.