Most likely to raise

Ice Bucket Challenge

Went viral: July-August 2014 Money raised: Over $100 million in July/August of 2014

While the source of inspiration is unclear, the (ALS) Ice Bucket Challenge involves a participant dumping a bucket (or vessel of some sort) filled with ice cold water on one's self to spread awareness and raise money for research of ALS. Once complete, they can challenge others to do the same or donate. Millions have been raised and there are thousands of viral videos, but only 10% of participants actually donate monetarily.