It doesn't get much crazier than ski abs. You'll be happy to hear that the modifications are demonstrated as well in the video below. Start off by doing as many of the hard ones while maintaining good form, after that, switch to the modified version. Don't worry, no matter which ones you do, you'll still get an awesome workout. What's more is that it only takes one minute and you WILL get stronger every day.
Hope your Monday is going well!