and made you say WOW! When I first heard Stevie Ray Vaughan's 'Texas Flood' I was floored!!! I just had to start playing guitar after that. That song was it for me.
SRV - TESTIFY !!! I can't say it's my favorite stevie's song now, but when i heard it i just couldn't believe it.
there've been lots and lots of songs that have done that to me. the one that continues to do so almost everytime i hear it is the acoustic demo of "Supersonic" (Oasis, obviously)
There's been a lot of songs that have done that to me as well. The one that has had the most impact on me is probably Voodoo Child (Slight Return) by Hendrix. Ever since I heard that song in 7th grade, I've been a music junkie. Now if I go for more than a couple hours without music I get really irritable, and start to lose it.