I should've posted this on May Day.....but there was a workers union for those who worked on the trading floor in Brazil at the BM&F in Sao Paulo which is now closed and a fully electronic market as of June 2009. The Sindicato dos Trabalhadores no Mercado de Capitais do Estado de São Paulo translates from Portuguese into English as "Union of the Workers in the Stock market of the State of São Paulo" and they even have a website which I linked on the union name above.
I got to visit the BM&F a few times and the most distinctive thing I remember was that there were ZERO women who worked on the trading floor. Brazilian women would be far too much of a distraction to get any work done so I can understand why there were none on the floor.
The following Bloomberg story does a good job describing the closure of the BM&F pits and is linked:
Brazilian Futures Pit Empties as Open Outcry Ends in ‘Sadness’