gSculpt is an open source, procedural subdivision modeller. It has a comprehensive set of polygon modelling tools, including most of those found in Wings 3D, and more.
Workflow and speed of use are important design goals in the development of gSculpt. Pre-selection highlighting throughout the program, and keyboard short cuts ensure that the workflow is fast and efficient, while providing access to a powerful procedural system which allows mistakes to be rectified easily.
Its procedural modelling system makes it an excellent choice for making modelling tutorials, as the steps required to build the model from the beginning are displayed to the user in a list. This list can be navigated easily, allowing a user to view the process one step at a time, at their own pace, while being able too look at the model from all angles as they go.
gSculpt can import and export Wavefront Object (.obj) model files.
George Supreeth has created a website called Painless 3D. His site has some very well written tutorials to help you get started with 3D and gSculpt.