David Richardson has created a multiple-part tutorial for modeling a mech in ZBrush.
Art for Games - Custom Alphas Tutorial
Art for Games have launched their game art education site, along with a new tutorial on custom alphas in ZBrush.
Ben Mauro - ZBrush for Environments
Ben Mauro has released a free 3D environment design tutorial using ZBrush, Keyshot and Photoshop.
Eat 3D - Character Production in ZBrush 4
Eat 3D have released a new video tutorial, focusing on Character Production in ZBrush 4.