Starship Marine

Starship Marines is an Starcraft boarding game done by Jim Wallman for minimum two players, with no limit in players. The game itself is a print and play type, and available for free download.

From the Introduction in the basic rules:
Starship Marine is a set of science fiction wargame rules, designed for use with toy soldiers. The basic idea is that there is a battle to control and capture a starship by a boarding party moving down the corridors and rooms of the ship. One side controls the attackers, who are mostly composed of the eponymous 'Starship Marines', and the defenders, usually less well armed crewmen, with perhaps a smattering of Marines to stiffen the defense. The deck plans can either be drawn out or built in 3D, depending on your preferences and time available. The scale of toy soldier is 25mm or 1/72, and any make of figures can be used [...]

The minimum you need are a few toy soldiers, some dice, a large sheet of paper with a deck plan on it, and the rules. A typical small game takes about a hour or so (longer if you like arguing about rules). The largest game we know of, to date, involved some 60 people, hundreds of toy soldiers, and many very very big sheets of paper.[...]