American Idol winner Ruben Studdard appeared and performed at the 3rd Annual Cinderella Ball at the Willard Intercontinental hotel in Washington, D.C. The ball is an annual prom-like event for students with disabilities, and is sponsored by The House, Inc.

Christina Aguilera and her erhm … “new friends” ((points at her boobies)) performed at the Stephen Webster Silver Collection Launch Event at PURE (Caesar’s Palace) in Vegas.

Singers Ashanti and Lloyd both hit up the “Ultimate Prom,” an event hosted by Hearst Magazines and Universal Motown at the Grand Hyatt in New York. Lloyd also performed.

Kenneth “Babyface” Edmonds, Christina Milian, and Diddy were all spotted on the red carpet at Prince’s release party for his new book “21 nights” at his L.A. home over the weekend. It’s been reported that Prince performed at the party for a whopping hour and 15 minutes! The concert was free for guests with invitations. The book is slated for a September 2008 release, and will cost $50. Pretty expensive if you ask me….

(PHOTOS: WIRE IMAGE)