I recently picked up a Wahoo Fitness Kickr Trainer. I am very pleased with how well this product works and how seamlessly it interfaces with all of my devices. I was also pleasently surprised to find out how many 3rd party apps are available to make the trainer do many different things.
The trainer makes doing any power based workout extremely easy (not less painful). One app, allows you to write a specific workout based on pecentage of FTP and then it will control the trainer using whatever FTP is entered. Start the workout, put on a movie, let the trainer do the thinking and all you have to do is keep pedalling.
There are other apps that allow the user to watch race videos, or course videos while on the trainer. The trainer uses the .gpx file from a gps device to simulate the course.
This trainer has made indoor rides a much more pleasent experience, and it allows for some amazing FTP testing. The Wahoo Fitness Kickr is by far the best trainer I have ever used.