rollerce:
The LED will be painfully bright at it's nominal voltage and will definitely provide me the powerful momentary flash that I'm looking for, and I willprobablywant to current limit it a bit just for the sake of reducing it's brightness somewhat.
Not probably - definitely. Consider a fully-charged battery, straight off the charger.
Otherwise, buy a good supply of those LEDs, because you'll be replacing them regularly.
Let's say the battery is at 4.2V. And the LED Vf is 3.8V. And the wire resistance is 10 milliohms. The current through the LED would be (4.2V-3.8V)/0.01 = 40A. (Or a bit less due to the battery's internal resistance.)
Those figures might be out a bit, (or a lot) but you get the idea.