If you have a product or service that can be sold in all 50 states, then national cable might be a good advertising vehicle for you. Buying Prime Time ads nationally are often times too expensive for small and even medium sized businesses. However buying early or late fringe remnant slots (before or after prime time) as well as overnights on smaller networks such as Antenna, Chill, Hallmark, Military, etc, can be highly effective for many advertisers that don't have the resources of large companies. You can test a national tv campaign for $4000 to $5000 per week, which can reach up to 40 million subscribers. If you search around you can have a company produce a decent direct response non-hosted ad for as little as $1500 - $2500.
We have done quite a bit of work for Mass Tort attorney's (i.e. Mesothelioma, Birth Defects due to antidepressants, Deffective Hip Replacement, etc.) using this model. We often start with a 5k per week 2 week remnant buy per category. If the campaign meets our cost per call parameters and cost per acquisition parameters, we will scale the buy, with often very strong results for our clients.
Of course you will need a call center to answer the influx of calls during certain periods. Don't try to save money and have your secretary and others in your office answer all of these calls, because they will often be overwhelmed at times. Also it makes call tracking more difficult. It's not that expensive to hire a service like Teledirect or Answer Connect and is well worth the money.
If you have further questions feel free to email or call Razor Edge Media.