In case you didn't watch the VMA's on Sunday night, Katy Perry wore a throwback denim dress to honor Britney Spears, when she wore a denim dress alongside Justin Timberlake years ago.

Well, Britney had the BEST response ever to when Katy tweeted to her about it!

You've gotta check it out for yourself below. Wouldn't you have loved to see Britney and Justin dress up and go together one more time, for old time's sake??