You're talking about the wok stir-fry vermicelli, am I right? Sometimes they have bits of eggs, chicken/pork and vegetables in there? If that's the case then in Singapore we call it Xin Zhou Mi Fen or Fried Beehoon. You piqued my interest so I googled it and came across this blog post http://maidsinmelbourne.wordpress.com/2012/10/19/why-this-singaporean-hates-singapore-noodles/comment-page-1/
Interesting what she says about the curry powder, because when I think about Singapore noodles, I don't think of all the ingredients to make the dish, I just think about the noodles themselves - the rice vermicelli. I buy the unprepared noodles from the shop - labelled Singapore noodles - and then make my own stir fry. I don't use curry power or oil, but soy sauce.
We have many vermicelli type of dishes in Singapore. Vermicelli can be fried or in soup, like a fishball soup, or the Malay/Indonesian chicken soup (Bee Hoon Soto). I usually order vermicelli in Singapore because it's the noodles with the least calories (if not fried in lots of sauce). Haha.