Working late and getting tired of seeing your coffee go cold while you're busy? The clever Sleepy Bear Cup warmer from Just Mustard can help you out with this! Place your cup on the coaster and connect it to your computer, using the USB cable. When plugged in, it will keep your coffee or tea warm, so you can focus on getting the work done. The cup warmer can also be perfectly used as a coaster for cold drinks like water.