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@bq
Blowing bulbs is pretty difficult on my Raleigh - you can't go fast enough to do it - well you could, but the brakes are so crap you don't tend to.
As always Sheldon has the answer:
I used to have a Dynohub on a tandem, and the bulb consumption was unacceptable. I solved the problem (and some others) by running the Dyno's output through a full-wave bridge rectifier and then hooking the DC in parallel with a 6 volt (5 x 1.2v cell) nickel cadmium battery. This not only provided light when I was stopped, the Dyno would re-charge the nicads, and, when we went so fast that the voltage rose above 6 volts, the low internal resistance of the nicads sucked up the excess, gaining a bit of extra charge and saving the bulb.
This is almost exactly the circuit that was in the Sturmey FSU by the way.
Once the voltage is sorted Halogen bulbs should not be prone to blowing. They keep going for decades in cars. One advantage is that you can easily convert existing setups with barely any electrical skill. 4 Nicad AA batteries and a rectifier would fit inside the front lamp of my Sturmey system. I may try it and report back