I had to laugh at this one, but I bet my neighbors really love me for this one!! !
I had a sewer clog in the main line from my house, so I went to the hardware store and bought about several bottles of sulferic acid and poured it down the drain. It got rid of the clog and washed it all the way down the pipe to the main under the street. Once it made it there, it seems to be reacting with whatever else in the main sewer pipe. I walked outside later on, and saw smoke coming out of the manholes and sewers on the street. The air was filled with the odor of rotton eggs!