Just got my crappie world mag, which had an article about fishing warm water discharges during the cooler months - I thought/heard about this before and completely forgot about it.
Most power plants are along major rivers and will have a hot water discharge. Google for power plants in your area and use the google satellite imagery to try and see where the discharge is located. The article said they can be successful up to several miles downstream of the plant - just watch your water temps. Fishing shallow - near logs and laydowns, especially around bends, was supposedly the way to go from what I recall.
Swan-Diving off the tongues of crippled giants