When jacking the rear of the car up, I just use the steel joints just after the jacking in point, kinda flat looking things with a circle hole in the middle of em.
As for the front, just those rubber grommit type parts a little past the jacking in point (altho they look a bit mashed! Not my fault there were already there lol).

Back on topic - mine did this last night, I braked at around 70-75 and the noise that came from the front left was quite worrying! Think the discs have gotta be changed!!!
 
Definately the discs if it's only under breaking. Same for me though :( Sucks, i wish it was cheaper to fix... bit it's not lol