http://www.gratuitoustankbattles.com/index.html?ref=positech.co.uk
Gratuitous Tank Battles is coming to the PC and Mac, developed by Positech Games, makers of Democracy, Kudos and of course Gratuitous Space Battles. Gratuitous Tank Battles is an RTS/Tower Defense hybrid with online elements and customisable units. The player can take the role of the defender or the attacker in a series of top-down explodey battles. A built-in map editor will allow easy sharing of custom maps and defensive challenges with other GTB players in a similar fashion to GSB's challenge system.
its slow and not initially gratifying in the same way as gsb, but that said i only played a few battles each way and still to start the unit building. Think this will grow quickly on me. must admit enjoyment at watch infantary getting churned up forlon hope style. The stratigy is deeper than gsb, after some more unlocks my aim for my attacking force is light fast infantry/light tank spam, with one or 2 huge rolling fortress type tanks.