Phantoms is advertised as a quick and easy air combat game covering the period 1960 to the present.
Scratch Building A 15mm Mortar
Here’s a tutorial on scratch building a 15mm mortar.
Torn Liveries Wars of the Roses Rules
Torn Liveries is a set of free wargames rules for the Wars of the Roses. The focus is on skirmishes, and the set includes rules for duels between leaders.
Paper Tally Wheels / Tracking Dials
A freebie from RPG Now is a pdf for creating your own tracking dials / tally wheels. They’re intended for Villains and Vigilantes, but they’d be perfect for a huge variety of miniature, board, and card game — anything where you have to keep track of hits, actions, mana or what-have-you.