I saw a dust devil once. Should have honestly been rated...nearly blew me over.
It was my senior year of high school back in 2006. I used to do the scorebook for the baseball team. It was a hot (but not humid) day with temperatures probably close to 90. There were no clouds and no breeze. All of a sudden this huge gust of wind kicks up and there were some leaves back by the corner of the school that were rising in a circular motion. It was coming at us. As it crossed into the gravel/sand it started to pick up rocks and dirt. It was an very strong burst of wind. Knocked the coach off the bench and it lifted the medical kit several feet into the air. As it traveled along the field the vortex easily extended hundreds of feet into the air and went clear across the field before dissipating at the end of the field near the road. It had also taken up my papers and you could see papers swirling hundreds of feet into the air. This is the best part...it took the umpires check and it was found the next day in Windsor, CT or Enfield (I forget which town). So it traveled in the air from West Hartford and was found in someone's yard. Getting pelted by the pebbles was not fun...well actually it was