Steam News announces a free weekend is now underway for Etherium, though they are underselling what is actually a free full week of play in the real-time strategy game, as it runs from now until the middle of Sunday. Here's word:

Etherium is a real-time strategy game set in a science-fiction universe, where three factions battle it out for a mysterious and rare resource known as ‘Etherium’.

Manage your resources, develop your base, and take command of infantry, tanks, aircraft, and gigantic colossi of war to battle not only your foes, but weather anomalies and mysterious secondary factions in richly strategic and original RTS gameplay. In the single player Conquest mode, develop your technological capabilities and expand your colonies over the furthest sectors of space, assembling a formidable armada.