I try to avoid making my teeth disgustingly white, because as both my dentist and former orthodontist said, "Healthy teeth are not naturally white. They're actually a little yellow." That being said, brushing after drinking staining things like coffee has always kept my teeth very nice.
My mother used Crest White Strips, and they whitened a little, but she said they made her teeth sensitive . She eventually paid the dentist to whiten then.
My grandfather had his own teeth til the day he died, and they were PERFECT teeth. According to my mother, he brushed his teeth with baking soda every night. I've since used Arm & Hammer baking soda-loaded toothpaste, and while it tastes a little funny, it DEFINITELY gets your teeth mega-white.