Gut Check Solo 15mm Science Fiction Rules v1.7

Gut Check is a set of free wargames rules for 15mm science fiction battles. What makes it unique, I think, is that it’s designed from the start for solo play. The author lists its features:

Designed from the ground up for solo play
Fast playing and zero bookkeeping
Uses normal 6 sided dice (Usually rolled no more than 2 at a time)
Uses activation rolls modified by battlefield conditions for turn sequence
Seamless Over watch and suppression effects built into system
Use any miniatures
Played on a Hex grid for convenience, but could be played with little fuss on a standard table

Three Plains 15mm Fantasy Wargaming

Three Plains is a new, and free, 15mm fantasy wargaming system. It also comes with free print-and-play figures.