I fucking did it again, just a few minutes ago. This time on a bike. I had the old brake pads out, i leaned on the handle bar to stand up and get the new ones because I'm old and managed to bump the brake handle against the wall with my body weight. The caliper piston shot out of there and mineral oil is all over the place, all over the rotor, all over me. So now i need to order a bleed kit for a bike, which I'd need eventually anyway but I'm just annoyed because I made this mistake years ago on a prius.