One example could be taking funds from the RDSP and investing them into a corporation owned by that individual. That would be a prohibited investment under the anti-avoidance rule.
Thus, you could put $100 into a registered disability savings plan, to use a simple example, keep it in there to access the marginal rates, and then when you want access to the money, you invest it in one of your private corporations. Let's say that it's $120 because you earned income over a number of years. You take that $120 and invest it in a corporation you control or lend it to a corporation you control or to yourself, and then the money ends up essentially back in the hands of the person who established it. Again, you can see that as being more enticing tax planning in the world of registered retirement savings plans and TFSAs, where income earned in the registered plan is tax free.