ID:182673
 
http://en.wikipedia.org/wiki/Erector_pili_muscle

So I guess people aren't suppose to be able to control goosebumps. I can voluntarily give myself goosebumps. I can make myself get a tingle in the base of my spine on my neck and I can get goosebumps whenever I want.

Do I win a special person prize?

~Kujila
I can imagine myself chewing on a brick and it gives me goosebumps. However, I don't think psychological control counts.
In response to Foomer
Foomer wrote:
I can imagine myself chewing on a brick and it gives me goosebumps.

"Go chew a brick" is one of my mother's stock expressions.

Lummox JR
I can somewhat do it voluntarily but not perfectly, sometimes when I try it I'll get stuck halfway between getting the chills and not getting them and I get kind of uneasy after that because my body wants that last little shiver (and goosebumps) from it to happen but it won't.
In response to Nadrew
Meh, same here, that's pretty annoying when it happens, I keep trying until I get it. Seems to be easier to do when it's colder, or you've got your shirt off or something, which makes sense, I suppose.
In response to Nadrew
I can think of the theme from the first movement of Dvořák's Symphony No. 9 and it gives me goosebumps. So, like Foomer's brick, it's semi-voluntary.