Beyoncé Knowles struck a very hot pose on set in LA yesterday. She's reportedly working on a music video as she gears up for the release of her fourth album later this year, and was spotted shooting in the Mohave Desert on Monday. The singer has been taking a break recently, enjoying her downtime with husband, Jay-Z, but she'll soon be back on stage. Beyoncé is set to headline the Glastonbury Music Festival in June, along with Coldplay. It sounds like the perfect chance for a collaboration with Jay-Z or Gwyneth Paltrow as their spouses take the stage. Jay-Z and Gwyneth swapped interviews and memories performing together this week as they helped celebrate his new website Life + Style and her cookbook My Father's Daughter. Beyoncé's also been focused on charitable causes, having recently created a new version of "Single Ladies" to aid First Lady Michelle Obama's "Let's Move!" campaign.