I have a CycleOps indoor trainer but I would also like to measure distance and need my front tire to move as I use the (back wheel) trainer....is there such a thing as a front-wheel-roller? or should I just relocate my wireless computer to the back wheel?
No matter how long you pedal, your distance on a trainer is zero.
Seriously, for less than the price of a front wheel roller, you could buy another cyclocomputer (cheapest one) and use it on the back wheel. You could leave the magnet on the bike, but make the sensor and computer part of your indoor trainer. Just velcro, tape or rubber band the sensor and computer on when you need it.