Here's a unique take on video tutorials used to explain some tougher topics. This video in particular explains Wikis. Produced by CommonCraft. Can't get any simpler than this and to me it does a great job explaining the subject.

Here's an interesting write-up that summarizes several sources of information about Amazon and high scalability systems. I thought some of the bullet points were pretty insightful...

• Between 100-150 services are accessed to build a page.
• Take it for granted stuff fails, that's reality, embrace it. For example, go more with a fast reboot and fast recover approach.
• Work from the customer backward. Focus on value you want to deliver
  for the customer. Start with a press release of what features the user will see and work backwards to check that you are building something valuable.
• Use measurement and objective debate to separate the good from the bad. Referred to as getting rid of the influence of the HiPPO's, the highest paid people in the room. This is done with techniques like A/B testing and Web Analytics. If you have a question about what you should do, code it up, let people use it, and see which alternative gives you the results you want.

Ran across this desktop program that shows your current song and album cover on your desktop. It works with several media players and its look can be customized using skins (view skin gallery).

The software is free and can be downloaded here.