I'm living in Sweden at the moment and here it's 112, but 999 also connects.
In answer to happy_face's question, it was changed for two reasons I believe.
1) it's harder to sit on your mobile and inadvertently dial the new 112 combination, as opposed to three consecutive numbers 000 (also children are less likely to press the new combination if playing with the phone).
2) on old bell and 'dial' phones, ' 0' was the last hole on the dial so in an emergency you had to wait for it to recoil all the way back round to the start position for each of the '0's dialled.
I've always believed this to be the reason, but will stand corrected if anyone knows differently.