Modify those popular box flashlights into a UV Blacklight or a red NightVision version. These cheap, bright torches have two light arrays, so you can keep a regular white light on one and turn the other light bar into a custom illuminator.
And they are very easy to hack. The smaller array is really easy to modify. Well, it's actually replacing or substituting standard 5mm LEDs into the case.
The mod takes about 10 minutes and
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