Meet IrukaTact: a haptic sonar glove that lets you feel sunken objects under water. Each finger has its own pump, which pressurizes water to give you feedback as you get closer to an object. The glove has a MaxBotix MB7066 sonar sensor, small motors, and an Arduino Pro Mini.
The closer you get to an object, the stronger the pressure becomes. Such a tool could prove useful when navigating flooded environments with limited visibility.