I've recently bought a whole lot of antique sidewall dynamos on ebay and hooked them up to modern LED lights. It's a decent balance between cost and effectiveness. The lights work absolutely perfectly. The drag is greater than with a dynamo hub, but I saved a ton of money. They also make a lot of noise, but I only run them when I need to. Plus, these dynamos weigh less than dynamo hubs, and installation was quicker and cheaper. So you don't even have to spend $60 on the dynamo if you don't want to!

I agree that battery tail lights are pretty fantastic and therefore you don't need a dynamo-powered tail light, but it sure is nice to have one. My Bianchi Volpe has a dynamo hub and dynamo-powered headlight and tail light. I just jump on the bike and go, without attaching anything or thinking about battery charge. It really didn't take long to wire up the tail light, and it was an investment that paid off. I sometimes supplement the tail light with a battery-powered blinky. I very rarely supplement the headlight. I let the lights run day and night on this bike, because the perceived cost (imperceptible drag) is so low.