Madonna, Beyoncé, Halle Berry, Tom Cruise and Katie Holmes ... the list goes on of A-list stars who descended upon Chicago Tuesday to wish Oprah Winfrey farewell at a taping of the talk-show queen's third- and second-to-last episodes ever of The Oprah Winfrey Show.

"Having fun?" Winfrey asked about 13,000 audience members packed into Chicago's United Center – which was stocked with 13,000 boxes of tissue – for the taping of two shows that will air May 23 and May 24. "So am I! So darn cool!" (Winfrey's final episode will tape next week and air on May 25.)

Tom Hanks, who acted as master of ceremonies Tuesday night, told Winfrey, "You are surrounded by nothing but love" before introducing a video of viewers talking about how their lives have been positively impacted by the talk show that's lasted 25 years.

"I feel the love, and I thank you for it," Winfrey told the audience at one point, adding that the viewers present and around the world "honor me in the deepest way possible."

"They have literally risen up to change the world," Berry said of Winfrey's viewers. "The essence of The Oprah Winfrey Show is that we're all more alike than we are different."

Cruise, who walked out on stage to the theme music from Mission Impossible, quoted Glinda the Good Witch of the South from The Wizard of Oz, and told Winfrey, "You always had the power [to change lives], and that is the lesson you brought."

His wife said her viewers have donated more than $12 million to Women for Women, which helps female survivors of war. "Oprah we love you," Holmes said. "We thank you."

Madonna was slightly less sentimental: "A lot of people are inspired by Oprah. I am one of those people," the singer said. "She has balls and a wealth of compassion, and I have learned so much from her."

And the end of the show doesn't mean the end of her positive impact. John Legend said via satellite that 25 new libraries will be built across the U.S. in Winfrey's honor, and Diane Sawyer took the stage to say that 25,000 oak trees will be planted across the country "to remind everyone to live their best lives."

The night was punctuated by live performances by some of Winfrey's favorite musicians. Introducing her new single, "Run the World (Girls)," Beyoncé told Winfrey, "Because of you, women everywhere have graduated to a new level of understanding of who we are, of what we are and most of all, who we can be."

Josh Groban and Patti LaBelle also serenaded Winfrey, continuing the Wizard of Oz theme with a heartfelt performance of "Over the Rainbow."