You've just landed the man of your dreams and a $2 million engagement ring. What do you do next? If you're Kim Kardashian, you grab your guy and jet off to Monte Carlo! Kardashian (in Lanvin) and fiancé Kris Humphries spent Memorial Day weekend mingling with the Prince of Monaco, taking in the annual Grand Prix auto race and walking the red carpet at the Amber Lounge charity fashion show. Kirsten Dunst also hit the road, landing in Turkey for a gala dinner in celebration of the Istancool cultural festival. Click through the gallery for more photos of stars at the weekend's hottest parties.