10 Useful Usability Findings and Guidelines summarizes research findings that have a practical impact on how we design interfaces. The article includes visual examples for these findings:

• Form labels work best above the field
• Users focus on faces
• Quality of design indicates credibility
• Most users do not scroll (but more and more do)
• Blue is the best color for links
• The ideal search box is 27 characters wide
• White space improves comprehension
• Effective user testing can be very cheap
• Informative product pages win
• Most users are blind to advertising

In addition, the article includes case study findings about typography (line height, space, length), blogs, forms, and portfolios. Worth a read!