 For Ferrell's appearance, Conan played guitar with the band and Ferrell sang "Free Bird" while reprising his "SNL" cowbell.Ferrell's wife, Viveca Paulin, together with Ben Harper, Beck, and ZZ Top guitarist Billy Gibbons, also joined the band for this final performance.Jay Leno returned to "The Tonight Show" following NBC's coverage of the 2010 Winter Olympic Games.