If you know, you know: The year was 2002, and Paris Hilton turned 21 in a dazzling, barely-there Julien Macdonald mini dress, complete with a sparkling choker necklace. The dress's Y2k, of-the-moment ...

This time, it's the turn of our favourite eclectic-dressing Sagittarius, Rita Ora.

Constructed from a layer of thin sheer tulle with pink satin boning, Rita's birthday dress featured a strapless, sweetheart neckline and fell all the way to her ankles in a figure-hugging silhouette.