I'm curious which hosting services you guys use, and why you chose to use them. I know of a few reputable services which I like for different reasons.

Site5 is good because they offer cheap hosting with many free technologies and have 24/7 live support.

1and1 is good because their interface is very easy to use and they also offer affordable hosting. They have good support as well.

What do you use and why? Are there any horror stories out there?