18. The Justice League

The team first appears in The Brave and the Bold #28 (1960). Although series featuring the League occasionally have garnered low sales, the team has been fairly popular with comic book fans since inception. The Justice League concept was loosely adapted into the Super Friends animated series (1972-1985) and more directly into the series Justice League (2001-2004) and Justice League Unlimited (2004-2006).
Throughout the years, the team, or segments of it, are called Justice League America, Justice League Europe, Justice League International, Justice League Task Force, and Justice League Elite.