In this age of LEDs, it might be worth reminding that in the event of EMP, an LED is just another solid state device that is susceptible. Having one or two incandescent bulb flashlights would be advisable.

Or keep some LED flashlights in a lead-lined box?

EMP is controlled by a Faraday shield. Any box made of a conductive material should do the trick. Radiation itself is mitigated by lead but since light bulbs are not significantly affected by any reasonable doses, there is no need for lead lined boxes.

Newcandescent.com sell some very HD incandescent light bulbs. Various wattage bulbs available, all designed for "rough service".

Good riddance to incans. LEDs are vastly superior in every meaningful way.

Except color rendition, for the vast majority of bulbs (though gradually improving).

How well do they warm your pipes if you put them under your house in a severe freeze?

LEDs are actually quite tough little solid state devices being essentially Diodes even when compared to very fine tungsten filaments. During an EMP the driver circuitry may become damaged but if they fail the LEDs can be removed from the housings and 4 LEDs can be arranged in series with a 12V battery such as an SLA to produce some light. Getting light out of an incandescent bulb even if perfectly functional might be a little more tricky during an EMP as access to a working inverter may prove a little more difficult. A butane gas powered soldering iron might be worthwhile purchasing. Repairing a vacuum tungsten filament is virtually impossible at home.

The LEDs will also typically last 5-6 times that of incandescent if using a limited power setup such as a DC battery (not including the inverter losses) before the battery dies (assuming that the battery even has the load capacity to even run a 40-100 Watt incandescent).

A backup butane gas powered light source/latern would also be a worthwhile having for an EMP event.

http://www.gasproducts.co.uk/acatalog/Bullfinch_1616_Handilight_Gas_Lantern.html

For general purpose lighting, a lantern or similar gas powered light would be suitable. The only alternative I know of besides rare bullseye lanterns would be a carbide lamp as a flashlight type replacement.

I marvel at all the comments about color rendition on candlepower forums - sounds like a bunch of wine connoisseurs comparing vintages. I am quite content to simply have adequate light when I mash on the button. Nuances of color are rather peripheral.