Scream one curse word, slam my fist into the nearest object, grab my fist, curse again, hop around on one leg, kick the nearest object, drop to the ground, curse again, knock my head out of stupidity on the nearest object, go KO.
This happened to me a few hours ago, only it was with my knee on the corner of our table. Funny thing is, it took me 3 seconds to realize what had happened.
I then dropped myself on the couch, pushing my hand on the spot of impact, while mumbling stuff like 'sh*t' and 'f*cking table*
I usually rub alcohol on the toe that got bumped then massage it in front of an electric fan, cooling it with the wind. Then I relocate the offending object that I bumped my toe into.