This week's Trends: cool covers, summer tunes, and little metal fans

Each weekday, we at YouTube Trends take a look at the most interesting videos and cultural phenomena on YouTube as they develop. We want take a moment to highlight some of what we've come across this week:

• We looked at the latest trend in cool covers: Katy Perry's "Last Friday Night."
  
  
• We saw dramatic footage of the fire in New Mexico and protests in Athens.
  
  
• We discovered the songs people were listening to around the globe.
  
  
• We tracked the top trending music videos of the week.
  
  
• We studied the most popular cat video that did not contain any cats.
  
  
• We enjoyed some of the littlest metal heads.
  
  
• And we took in this beautiful scene from a Summer Solstice holiday in Poland:

Check back every day for the latest about what's trending on YouTube at: www.YouTube.com/Trends

Kevin Allocca, YouTube Trends Manager, recently watched "Major League Savings."