Wish I had done this with the only frame I've tried to get a seatpost out of using more than brute force and penetrating oils. I used hacksaw blades and a sawzall to cut strips out of the post. I started carefully but got super complacent because it was taking forever and sawed a hole through the frame like an idiot. I laid out a book on the workbench and just went on autopilot with the sawing. It was a lower end Univega that someone else had already given up on, but I still felt like a complete idiot when I looked down and saw the tip of the blade starting to poke though the seattube.