The only human enhancement device I use currently is a pair of eyeglasses. I have friends though with pacemakers, hearing aides and metal hip joints. (You can get a feel for age of my peers by looking closely at those items.) I often imagine what the next generation will have available to help them out.
Heck but why let the next generation have all the fun. Here is a list from Dvice of some other items you could have implanted to improve your biology today. The device shown here isn't implanted but it allows you to control the robot using just your mind. Cool. Kind of bulky for the front room. But, still cool.
[Image captured from http://dvice.com/archives/2009/05/8-body-implants.php]