Beyoncé gave a powerful performance of "Halo" during Friday's (January 22) "Hope for Haiti Now: A Global Benefit for Earthquake Relief" telethon.

Performing from London, the songstress was accompanied by Coldplay frontman Chris Martin, who performed with his band earlier in the night, on the piano for an acoustic rendition. Beyoncé injected Haiti into her lyrics: "Haiti, we can see your halo/ You know you're my saving grace," she sang. "You're everything I need and more, it's written all over your face/ Haiti, we can see your halo/ I pray you won't fade away."

The emotional track is from her 2009 LP, I Am ... Sasha Fierce. B is one of a long line of participants for the telethon, including her husband, Jay-Z, who performed later with Rihanna and U2.

Learn more about what you can do to help with earthquake-relief efforts in Haiti, and for more information, see Think MTV. Visit HopeForHaitiNow.org or call (877) 99-HAITI to make a donation now.

iTunes customers can exclusively pre-order the "Hope for Haiti Now" full-performance album ($7.99) and the full two-hour video telecast ($1.99). Pre-orders will be delivered in the days following the telethon. Individual audio performances will also be available for purchase and download for 99 cents each in the days following the telethon. Apple, the record labels and the artists will donate their share of the proceeds to Haiti relief funds managed by "Hope for Haiti Now" charities, including the Red Cross and Wyclef's Yele Haiti foundation. Performances will also be available for purchase in the days following the event through Amazon's MP3 service and Rhapsody, through distribution provided by INgrooves.