No Man’s Land is a solitaire card game that’s supposed to simulate being a sniper in the Great War.
Roundwood’s World has an excellent photo illustrated post on how he built a trenches terrain board. It’s something I’ve always wanted to do.
In 1/72 and 1/48 scale, here is a downloadable model of an Albatross DRII.
If you’re out of game ideas, here’s a scenario generator for Spearhead: Great War.
Iron Hands has an illustrated article on making trench systems for your 25mm – 28mm miniature wargames. The principal ingredients are concrete patch, rocks and fiberboard.