How about powering a night light for starters?
We looked further and found a dealer who sells in units of 100 and he wants $2.30 for each light.
Best price I could find on the net for a traditional incandescent candelabra light with same lumens rating was $1.07 each.
What this means is the price of LEDs is falling like a rock!
The power consumption of an LED is remarkably low ~ many of the experimental set ups should be able to light one up.
We'll hold you to this one ~ an LED on an LENR operating unit.
Actually, this might be a fairly good test for almost any power source ~ to wit: However you can do it convert your excess heat or photons to electricity sufficient to charge up a fast charge microminiature battery sufficiently to power a 1 ma LED for 1 min.
Even a Tokamak can't meet that standard!
Too easy to fake...