Acoustic songs.

[YI]

All of these are at least acoustic based, but some have other layers on, but could be de-layered/isntrumental played about with to make it work.

"Tests On My Heart" by Umbrellas.

"Turn Out The Light" by The New Amsterdams (Not sure how it'd work on one acoustic though, it could be done, but mightn't sound that great)

"Rain Song" by Sunny Day Real Estate

"She is Love" by Oasis

"Champagne Supernova" by Oasis (me and a buddy did a 'good' piano/acoustic version,so It's workable)

[ADG]

"Grandfather" by Stephen Lynch

[Skummy]

"You Suffer" by Napalm Death. I've played it in acoustic sets before, goes down a storm.

[Steeb]

Just remembered. Do 'John Wayne Gacy Jr.' by Sufjan Stevens.

[Cactus Drags]

Sic Transit Gloria by Brand New. Or any of their stuff that's actually acoustic.