What fictional tech do you most want to become real?

Sometimes fictional technologies become reality (submarines! tablet computers!) and sometimes they remain firmly in our imaginations (where is my tricorder, future?). Today, we want to know what fictional tech you most want to see inspire a real world invention.

Tell us in the comments what fictional invention you most hope to see become reality, where it comes from, and just what you would do with it.

Image: Data uses a tricorder.