Kareem Abdul-Jabbar
In 1975, Kareem Abdul-Jabbar was traded by the Bucks to the Lakers and in return they got Junior Bridgeman, Dave Meyers, Brian Winters and Elmore Smith. Despite the fact that Meyers and Winters were good players, the Bucks lost their greatest big man of all time while he was in his prime. The Lakers were led by Kareem to five NBA titles in 14 seasons. In his career, he had a remarkable average of 2.6 blocks, 3.6 assists, 11.2 rebounds and 24.6 points per game. He also became the winner of six Most Valuable Player awards. >
McHale and Parrish
In 1980, McHale and Parrish were traded by Golden State Warriors to the Celtics and in return got Joe Barry Carrol. McHale continued his career remarkably and ended up with statistics of 1.7 blocks, 7.3 rebounds and 18 points per game. He also had an impressive 55.4 percent average from the field. Parrish participated in 1611 games which are the maximum for any player. His statistics were 1.5 blocks, 9.1 rebounds and 14.5 points per game. Both these players were inducted into the Hall of Fame and are considered as two of the greatest big men of all time.
Scottie Pippen
In 1987, Scottie Pippen was traded by Seattle Supersonics to Chicago Bulls for Olden Polyince. Pippen assisted the Chicago Bulls to six championships in the 1990s. He was regarded as one of the greatest all-around offensive player as well as perimeter defender. In 1996, he was chosen as one of the 50 greatest players. His career shows statistics of 0.8 blocks, 2 steals, 5.2 assists, 6.4 rebounds and 16.1 points per game. He was also chosen in 7 All-NBA teams and 7 All-Star teams out of which 3 were first team selections and 10 All-NBA defensive teams out of which 8 were first team selections. 
Kobe Bryant
In 1996, Kobe Bryant was traded by Charlotte Hornets to Lakers and in return got Vlade Divac. Further, Bryant became one of the ten greatest players of all time when he was 30 years old. He is looked upon as one of the greatest defensive and offensive players of all time. The statistics of his career are 1.5 steals, 4.6 assists, 5.3 rebounds and 25 points per game. He has been selected to the All-NBA defensive team and several times to the All-NBA first team. He has also made 10 All-Star appearances. 
Dirk Nowitzki
In 1998, Robert Traylor was traded by Dallas Mavericks to Bucks and in return got Dirk Nowitzki. Traylor appeared in 438 games with the Hornets, Cavaliers and Bucks and his statistics were just 0.7 assists, 3.7 rebounds and 4.8 points per game. At the other extreme, Nowitzki surged ahead to statistics of 2.7 assists, 8.6 rebounds and 22.4 points per game. He was regarded as arguably the greatest European NBA player of all time. So far, he has been chosen 8 times to the All-NBA team out of which thrice to the first team and 7 times to the All-Star game.