Do Your Bidding: The latest Grammy charity online auction is in honor of the 13th annual MusiCares Map Fund benefit concert honoring U2's Adam Clayton. Presented in partnership with Matchfire, available items include guitars signed by Kenny Chesney and Kacey Musgraves, a microphone signed by Carrie Underwood and a CD signed by Cam. Bid now through July 8 here. Proceeds benefit the Grammy Museum Foundation and MusiCares.