Another one I will plug, simply due to some recent interaction with them at my job, is Rackspace; specifically their "cloud" offerings (I put the word "cloud" in quotes simply because what they offer in that arena only matches their definition of a "cloud" - which seems loose to me).
Their online chat support was fast and responsive, very helpful, and even telephone support turned out to be the same, and knowledgeable about their product vs. your needs. In the end, we didn't use them (it didn't fit our client's needs, ultimately), but from what I saw, for the majority of uses, the cloud hosting and/or the cloud servers would fit a lot needs well (and it wasn't very expensive, either).