What are some cool things you have done or seen while playing D&D ?

Once, as a Wizard, I was using spider climb to climb along a ceiling, while moving silently over a room full of monsters, and my hand pulled a stone loose and it fell. Rolling a 20 on a reflex save, I quickly cast Mage hand to catch the stone in mid-air and brought it back up to me, remaining quiet the entire time. :)