4. Lance Berkman
Berkman played 11 seasons for the Astros, amassing a .943 OPS over his career and a 52.0 WAR. He is probably one of the greatest hitters of all time, and would make five all star teams while in Houston, finishing third in MVP voting in both 2002 and 2006. He would later go on to win a Championship in 2011 with St. Louis.