Filburn v Wickard (or vice versa) needs to be shot down, Big Time.
For those who don't know the details, an Ohio farmer (Roscoe Filburn) grew "too much" grain according to the dictates of the feds and the "Agricultural Adjustment Act of 1938". Roscoe responded that his grain did not cross state lines, and thus wasn't falling under the "in interstate commerce" clause of the Constitution, and therefore could not fall under Federal jurisdiction. (You see, this is back when the FedGov was actually limited and people paid attention to silly little things like the Tenth Amendment... This case is one of the ways that Pandora's Box got opened.) In fact, Roscoe wasn't even selling the excess grain... he was feeding it to his own livestock. It wasn't even leaving his property!!!
Unfortunately, the problem was FDR's lovely threat of "packing the Court" (in 1937) if they did not uphold his desires to be Emperor of America. (Since there is no stated limit to the number of Supreme Court Justices in the Constitution, his threat was to nominate 10 MORE Justices to add to the 9 life-timers on the Bench, and he would make sure that all ten were 100 percent under his control, so that every case would be decided his way, by at least a 10-9 vote. Aren't Democrats lovely?)
So, the Federal District Court sides with Roscoe, because they've actually read the Constitution before. Cowed SCOTUS overturns it, and upholds the Act under the Interstate Commerce Clause, saying that if Filburn had not used home-grown wheat, he would have had to buy wheat on the open market. This effect on interstate commerce may not be substantial from the actions of Filburn alone but, through the cumulative actions of thousands of other farmers, it COULD become substantial. Therefore Congress could regulate wholly intrastate, non-commercial activity if such activity, viewed in the aggregate, would have a substantial effect on interstate commerce, even if the individual effects are trivial... in other words, if ANY activity COULD somehow affect interstate commerce (like the flapping of a butterfly's wings in Africa), then the Feds could regulate it under the "interstate commerce clause".
And here we are, 70 years later, with the Feds in EVERY aspect of our lives. History lesson for today. :)