Assume you will have children, or don't (if you had them already). What music that they wouldn't normally be exposed to (so, not anything commonly played in movies, radio, in stores) would you have them listen to?

And at what age?

I really need to put some more thought into the coming months/years. Right now, we have our 7-month-old listening to classical for the most part, but I do mix in The Innocence Mission's children's album (Now The Day Is Over) some evenings, along with some kid-friendly tracks from other artists ("Meeting Mr Miandad" from The Duckworth Lewis Method and "Hoodoo Voodoo" from Billy Bragg & Wilco come to mind).

My kid has been listening to music from day one.

Pretty much everything, Rock, classical, jazz, new age, top 40

Slayer!

The complete Anal **** discography.

My son is 7 and has listen to my music since birth. He listened to classical as an infant. He has picked up his favorite songs from stuff he hears from me and tv/movies. So far his favorites include:
Flight of the Conchords
The Ting Tings - Happy Birthday (Yo Gabba Gabba)
Of Montreal - Wraith Pinned to the Mast (his current favorite)
Snoop Dogg - from Nickelodian & Gorillaz
Tom Waits - I don't wanna grow up
Yeah Yeah Yeahs - Pins
Black Sabbath - Iron Man
Gorillaz
Peeping Tom
Biz Markee - Yo Gabba Gabba

Expose them early and to as much as possible. I do try to steer him away from generic, bubble gum, pop crap. He never hears the radio w/ me, just the iPod.

I've exposed my kids to all kinds of music since they were babies and they love it. My five year old son is a big fan of The Beatles, KISS, Faith No More, The White Stripes, The Ramones, Kaiser Chiefs and plenty more. As far as music he "normally wouldn't be exposed to", he is especially a fan of The Damned's "Machine Gun Etiquette" album. Don't know where he would have been exposed to anything off of that LP at his age if it wasn't for me.

I play a lot of Beach Boys and Beatles for my daughters. My 4 month old responded very well to disc one of the White Album last weekend. She seemed very "up" through the whole thing.

I played all the same stuff for my 3 1/2 year old. Eventually moved to some 10,000 Maniacs, English Beat, David Bowie. I just try to keep it mellow, and "mellow" to me is older stuff, pre-'90s. I played the Pixies for her and she said it sounded "noisy". Eventually she found stuff she liked and gravitated to the Wiggles who aren't too bad as far as children's acts go. I've heard far worse.

My wife is a corrupting force. She plays all the horrible "sing a long" row your boat shit when they're in the car together, and the radio. My daughter decided one day that her favorite song is what she called "The Oh-oh Song" which took me a while to realize she was talking about Britney Spears' Till The World Ends. Oh great! Maybe it's not too late to save the four month old.

Similar story for me; I've attempted to expose my 3.5 year old to a variety of music. Recently I've been playing a bunch of Grateful Dead for her (yes, I'm attempting to make her a hippie); she's able to sing a long with a few of the songs at this point, which has me pretty stoked.

6 year old girl
Manu Chao (specifically Radio Bemba)
Queen
Sam the Sham (don't ask ;-)
Cindy Lauper (oh dear...)

1 year old girl:
nothing in particular yet. She enjoys music, but I need to work on getting some non-regular stuff to her.

I think what I find interesting is that when I was growing up, my dad would play stuff from Led Zepplin, Pink Floyd, Fleetwood Mac, The Beatles, and other bands of that time and I hated listening to it back then.

However, now, that I am older, I can appreciate the music and find myself listing some of the bands he played as among the top groups that I like. I've pretty much been able to listen to what I want since I was young, some of the choices my parents might not have known about or approved of, but they never really questioned my music because 1) they didn't have to hear it, and 2) I was never a trouble child or had any disciplinary issues.