I have a situation where I would like to have two thermostats controlling the furnace. There is no cooling system involved, just heating.

Does this require any special type of controller? Or is it possible to just hook the two thermostats in parallel to the furnace?

You can hook up 2 thermostats in parallel, but the thermostat in the area of greatest heat loss will really be the only one controlling the furnace. Without properly zoning the system, the other thermostat area will probably always be to warm then. So essentially you can accomplish the same thing by turning up the current stat. Turning the fan contol on the stat to on, will help even out the temperature in the whole house.