A water-light graffiti pop-up interaction is a great way to try something new for an evening check-in session

Water-Light Graffiti: a magical board marrying water and light that kids and adults want to try. Thousands of water-sensing LEDs; draw with brush, spray, water gun, fingers or towel. Images fade as moisture leaves. As a gala check-in, guests can improvise and photo with their fleeting works.