GoDaddy
I use GoDaddy as the registrar for all of my domain names, and I refer other people to them for cheap, simple, turnkey web hosting. However, in this one case, GoDaddy inadvertently charged me for a service, Website Tonight, for which I never enrolled. After logging into my account and cancelling it, I wrote to their customer support organization and demanded the credit card charge be reversed. They complied but never explained why or how the service was opened on my account.