http://www.artima.com/weblogs/viewpost.jsp?thread=188683

ebay has some very impressive stats ...

• 212,000,000 registered users
• 1 billion page views per day
• 26 billion SQL queries and updates per day
• Over 2 petabytes of data
• $1,590 worth of goods traded per second
• Over 1 billion photos
• 7 languages
• 99.94% uptime

even if you don't run ebay, amazon or google, lots to learn here. check out the presentation slides.