What are your favorite customer support sites and why?

What I'm doing
I'm doing a review of customer support sites, looking mostly for software (desktop and web) and services-related sites that provide a customer support site for getting answers to questions, and viewing documentation and tutorials.

Why I'm doing it
Some sites have better search capabilities for questions than others. Other sites do well at presenting documentation. I'm finding that there's sometimes a difference in how companies handle giving answers to the most granular questions as opposed to presenting a unified view of a product via a manual-like experience. There's a smaller/larger need, first time/experienced user dichotomy of needs, among other different descriptions of how and why a user approaches a support site. The need may range from "How do I do X" to "How do I get started using this" and every grayer need in between. I'm currently involved on a project where this is the problem we're faced with as the company has gone through several stages of growth, and needs to evolve legacy content and systems.

Can you help?
What are you favorite support sites in terms of these kinds of needs? I'm going to screen capture and review a handful of them here and show a cross-site comparison of capabilities. As a bonus, I'm doing a giveaway of a couple sketchbooks from those who comment.

Please give me the name of the company and the URL for the support site. And thanks for helping out!

Some of my starting points