A group of the world’s renowned musicians signed this guitar, auctioned in Qatar in 2005, to raise funds for tsunami victims, according to a press release. Signatures include Mick Jagger, Keith Richards, Eric Clapton, Brian May, Jimmy Page, David Gilmour, Jeff Beck, Pete Townsend, Mark Knopfler, Ray Davis, Liam Gallagher, Ronnie Wood, Tony Iommi, Angus & Malcolm Young, Paul McCartney, Sting, Ritchie Blackmore, Def Leppard, and Bryan Adams. It was bought by Qatar’s royal family earlier that year, donated back to the charity, and sold again for $2.7 million.