> How about an NTC thermistor
> whether you could find a suitable thermistor

Aye. The bulb still needs around 60W

> Alternatively you can get an opto isolators with built in zero crossing
> detection and relatively high power triac outputs.  Might be able to
> rig one of these up to ensure your lamps always get switched on at
> the zero crossing point.

Got some MOC3041's left over from a job. That would be the non-
s/w solution to zero crossing - but zero crossing needs to be done
only once, at turn-on. After that the bulb can shine on unimpeded like
a good'un. Ideally start at the zero-cross and ramp up to a V slightly
lower than full mains

There's a technique used in display matrices of pre-heating filaments
by giving them a quick flick of power for bits of a few cycles. I wonder
if this would extend bulb life by alleviating any thermal shock or is this
getting too geeky ?

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