Gary Bongiovanni, editor of Pollstar, says the success of auctions will depend on how they’re perceived by the public and by artists concerned about how auctions affect their image. No one wants to appear greedy, which is why there has yet to be wholesale adoption of the auction system.

Major acts, however, can turn auctions into public relations assets. For instance, since April, more than 100 acts, including Madonna, Tim McGraw and Faith Hill, Elton John, Toby Keith and Bonnie Raitt, have participated in Music Rising, donating tickets for Ticketmaster auctions to raise funds to replace musical instruments and equipment destroyed during the Gulf Coast hurricanes Katrina and Rita.

Through May, the charity had helped up to 1,500 musicians, including providing a new Baldwin piano for the legendary Fats Domino. Gibson’s Music Rising guitar, a limited-edition Les Paul made from wood from the devastated area, quickly sold out; a more affordable, larger edition of a Music Rising Epiphone Casino, the guitar used by John Lennon and George Harrison in the Beatles’ early years, is in the works.

Trent Reznor of Nine Inch Nails has been putting as much as 10 percent of his tickets up for auction, with money bid in excess of face value donated to the Innocence Project, a nonprofit legal clinic that does post-conviction DNA testing. Premium seats and meet-and-greet passes for most of Raitt’s shows are being auctioned for environmental causes at Charityfolks.com. Other musicians donate front-row tickets to Ticketmaster.