what is this song about?

This song has been on my head for 3 days straight.I have'nt heard it in years.I know david bowie also sings it.In a nutshell what's the meaning of this song?Winner gets 3 free beans.[YOUTUBE]fregObNcHC8&feature[/YOUTUBE]

....awe it's in gray to me...LOL, I found a thread on it >>>> http://www.sing365.com/music/lyric.nsf/The-Man-Who-Sold-The-World-lyrics-Nirvana/C690B623656ABC66482568510012EDE0

Well im not suicidal, or a dope fiend,etc...