Ben Affleck went casual during an errand run in Santa Monica yesterday. He stepped out in the middle of his latest challenge: living on $1.50 a day to raise awareness about extreme poverty. Ben announced earlier this month that he would be joining the Live Below the Line movement and will try to scrape by on $1.50 a day from Monday, April 29, through Sunday. He announced over Twitter that he's participating in the challenge on behalf of his charity, Eastern Congo Initiative. Before his poverty mission, Ben had a fun family day with his daughters and wife Jennifer Garner over the weekend. Ben and Jen cheered for daughter Seraphina during a track meet with a group of other children, and also visited a farmers market.