Throughout the first leg of the "Innocence + Experience Tour," U2 has switched up its nightly set list to a certain extent; songs like "Bad" and "One" have come and gone, rotated in and out of the concert batting order. It gives hope to fans who might be hoping for a more obscure favorite track to make an appearance on any given night.

For fans of some songs, though, there is little to no hope. Despite playing thousands of concerts all over the globe during the course of 35 years of touring, there are still some U2 songs -- even quasi-popular ones -- that have never gotten a live adaptation. If one of these five songs speaks to you in a deeply personal way, the odds are high you'll be disappointed:

'Acrobat'
One of the emotional centerpieces of "Achtung Baby," it's the only song from that album to never have been performed live.

'Red Hill Mining Town'
The only "The Joshua Tree" track never to see a live performance, it is rumored to have been one of the last songs cut from shows recorded for the film "Rattle and Hum."

'Holy Joe'
When U2 announced its PopMart tour from the lingerie section of a Kmart in Manhattan (the '90s were weird), it performed one song, this b-side to the "Discotheque" single. It's never seen the stage -- or a rack of bras -- since.

'Numb'
Poor The Edge. The guitarist gets his time in the spotlight with a rare lead vocal performance, and it comes on one of the band's oddest, most divisive catalog entries. It hasn't been performed live since 1993.

'The Wanderer'
Good news: You may hear it at Madison Square Garden. Bad news: It will be a recorded version, with images of Johnny Cash on the video wall. Its only live performance came during a soundcheck, recorded for a television special.

Special thanks to the indispensable U2 tour database U2Gigs.com for the statistics and set lists.