I once ate too much red velvet cake, and had the experience of pooping a bright red. Yes, it was a bit shocking, but funny once I knew what happened. If I were expecting it, I'd have been able to delight in the weirdness.

I got the chance to do this later on, however: I took a medicine for a urine tract infection which made my urine look nearly neon yellow. I knew it was possible, and it wasn't a big deal. Expecting the color change makes a difference.