Video: '30 Rock' high fives

Our pal Mark Malkoff is always up for a challenge: For example, once he visited 171 Starbucks locations in one day. Another time, he lived in an IKEA and made a video about it.

For his latest feat, Malkoff and comedian Kerri Doherty visited Silvercup Studios in Queens, N.Y., where 30 Rock is filmed. Their goal was to high-five as many 30 Rock cast members as possible - and they do a pretty great...