Using a broker such as Lightspeed, routing a 1,000-share buy limit order on the NYSE will currently net you $0.0014 per share. Lightspeed’s base rate is $.0045 per share, so the original $4.50 trade now becomes only $3.10, thanks to a $1.40 rebate from the NYSE. Note, however, this goes both ways, as routing a straight market order to the NYSE instead would incur a charge of $.0027...