Bulb - looks just about exactly like this one:
But instead of them being $5-14 each, I found them for $.20 each.... and they have cases of broken ones and I was wondering what the inner metal part is and if it could be used in custom glass blown bulbs like back in the Edison days when bulbs never died...
I was wondering if this could be run on rectified DC from 120AC. Isn't there something like a 1.4141 conversion rate from AC to DC rectification? 120 * 1.4141 would give just above 165v
This looks exactly like the heater inside a laser printer. It is not an arc lamp, it doesn't need high voltage (2 kilo-volt or more mentioned in some comments) to start.
It is purely resistive, like any resistor, and work well in AC (60 Hz, 400 Hz or any other frequency).and DC. Like any incandescent lamp, the resistance when cold is about 15 times lower than hot, so it draws a large current in the first 16 to 32 milli-second powering up. When using a dimmer, the Triac has to be rated to that worst case value ... and some margin more to cover voltage spikes.
As mentioned in many comments, it doesn't hurt to operate this halogen lamp below specification if the goal is to produce heat. The amount of heat generated is exactly proportional to the power used. The life time of the halogen lamp should extend in a non linear way. For example, if the bulb is specified at 10000 hours if operated at 1000 watts, it should last may be 40000 hours if operated at half power, 500 watts. It should last more than 100 000 hours if operated at a quarter of it's spec power, 250 watts, etc
However, if the bulb is used for light, then it has to be operated exactly at rated voltage/power for maximum efficiency. The light output is not linear with power consumption. If we provide half power (for example, 500 Watts instead of 1000 watts), we get much less than half the light output. The wavelength shift toward yellow, then orange, and the total amount of light in lumens decrease at a much higher rate than the ratio of power consumed/power specified.
