The Gratuitous Tank Battles Website now offers a playable demo for this RTS/tower defense hybrid follow-up to Gratuitous Space Battles. There are no details on what this sample of the game includes, so here's a reminder of what the game itself involves:

Gratuitous Tank Battles is the spiritual successor to indie hit 'Gratuitous Space Battles', the 'hands-off' battle simulation set in a universe at perpetual war. GTB is set in an alternate earth history where World War I never ends, and Axis fights Allies across Europe in the year 2114 complete with a mix of Tanks, Infantry and futuristic mechs.