El Segundo-based Internet mailing and shipping company Stamps.com was this week’s biggest mover, gaining 41.87 percent to end at $211.25. Boingo Wireless was also among this week’s biggest movers. The Los Angeles-based Wi-Fi company rose 29.71 percent to end at $19.21. Enterprise software company BlackLine Inc. was this week’s biggest loser, dropping 22.17 percent to end at $30.43.