This week's Trends: mobs, ads, and Passover

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 featured YouTube's top 10 most-viewed flash mobs of all time.
  
  
• We examined how T-Mobile's "Royal Wedding Entrance" took off with viewers and discovered popular ads from other countries around the world.
  
  
• We heard how a tornado... stole a man's hamburger.
  
  
• We saw unexpected hail videos were popular in Mexico.
  
  
• We witnessed dramatic tornado footage from America's Southeast.
  
  We closely followed the events in Syria, tracking on the scene videos of reported violence and widespread protests.
  
  
• For Passover, we pulled together 5 popular videos from a recent trend: Jewish holiday a cappella.
  
  
• And we enjoyed this surprising, lip-synced music video from some soldiers overseas:

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