Jessica Alba [1] served a serious dose of '90s nostalgia on Friday night when she shared a photo of herself and BFF Kelly Sawyer [2] dressed as the characters from Romy and Michele's High School Reunion. The pair wore Romy and Michele's now-infamous metallic minidresses, and Jessica kept things super authentic by donning a blond wig. She captioned the cute snap with a line from the hit 1997 movie, writing that they "invented Post-Its." Check out Jessica's costume now, then see more of the best celebrity Halloween looks [3].