Alas, 3-E Learning was a web resource for experiential exercises in entrepreneurship but it seems to be closed down now. They also offered a prize for submissions of the best exercises and tools for teaching entrepreneurship. This looked like a really nice resource. It would be great if people can re-post some of the best exercises here as well. Please feel free to submit if you have run any of them in your class (but be careful to attribute credit to the original authors and provide links to the original post).