> given a 100% efficicient converter from 1.5V to 5V (which of
> course doesn't exist), drawing 500ma out would require 500ma*
> 5V/1.5V = 1666ma input current (TANSTAAFL!).

ISTR Tomas reckoned 800mW for the circuit, so the conversion
process might explain the "Why not millwatt hours ?" thread

800mW out will be (800mW/conversion efficiency) in, more or less.
533mA @ 1.5V would be drawn from the AA to make 160mA @
5V, giving a realistic lifetime of 3-4 hours at a reasonable conversion.
Less battery current when fresh than when it's running out of puff. I
think battery capacity rating is down to 1V terminal voltage but you'd
have to check that

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