Staying hydrated while you work out is very important. There are plenty of backpack hydration systems around, but they are not perfect. The HYDRAfitt Pullover Hydration System is designed to keep you comfortable and hydrated. It is easy to fill and comes with a host of useful features such as pockets for your things.
HYDRAfitt is comfortable to wear and could prove useful on hot and cold days. More information is available on Kickstarter.