I just got a trainer so that I can train indoors for the winter and now my Cateye Wireless computer is useless because it works on the front wheel (would it work if I moved the sensor to the rear wheel, or would I then have to move the display to the back too, making it pretty useless). I'm looking for something that operates from the rear wheel, records speed and mileage, and that also does cadence since I'm working a little more on that on the trainer. I prefer wireless, but would consider something wired. Most importantly it needs to be cheap. After buying the trainer, my wife will probably send me packing on the bike if I spend much more.