There are a few notable players named Anthony Johnson in NBA history:

Anthony Mark Johnson: This Anthony Johnson is likely the most well-known. He played point guard for several teams throughout his career, most notably the Portland Trail Blazers and the Orlando Magic. He holds the distinction of being the first NBA D-League player to participate in an NBA Finals (with the Magic in 2009).

Other Anthony Johnsons: There are a few other Anthony Johnsons who have played in the NBA, though to a lesser extent. These include:

Anthony David Johnson: A center who played briefly for a few teams in the early 2010s.

Anthony Johnson: Played for the Los Angeles D-Fenders in the G-League (the NBA's developmental league).

Anthony Johnson (undrafted): Never played in an NBA game but was on some NBA teams' rosters.

Without more information on which Anthony Johnson you're interested in, it's difficult to provide specific details about their "interesting thing." However, Anthony Mark Johnson's journey from the D-League to the NBA Finals is certainly a noteworthy accomplishment.