In a nutshell a 'wonderbra'.
Looking from the outside everything looks big and exciting, much like the millenium dome.
But once inside you're massively disappointed, and soon realise that it's nothing you're going to be writing home to your mates about.
Bloke 1: Epic knockers!
Bloke 2: it's a farce, they're millenium domes.
Tits that look good from the outside, turn out to be nothing but fried eggs underneath the push up bra.
Check out the millenium domes on her.