Simple but very useful. This is a set of 3D printed parts that combine:
• A Dewalt connector from thingiverse, with some modifications
• A cheap 12-24V input 10W LED floodlight
• Various 3D printed mechanical parts
• My micropower undervoltage lockout circuit

It's been through a few iterations with size adjustments and small mechanical tweaks, but it works well and I have now made four of them.

I was also toying with the idea of putting a micropower LED blinker in the assembly, so I printed this one with a clear middle section:

And now the OpenSCAD:

• Initial version
• Longer version, more comfortable to hold
• A trimmed-down version of the base, adapted for M4 fixings
• A spacer which goes between lamp top and the base to make room for the undervoltage lockout circuit

All of these need some OpenSCAD libraries to use.