"It's a piece of art on the door of two robots, and it has a very significant story between me and Steve Molaro and so I will be taking that," Cuoco told PopCulture.com's Scott Huver at the Television Critics Association Press Tour, while referring to the Emmy-nominated producer.
"It's just kind of a little bit of a personal story between Steve and I, but we have a connection over it and he has the original, and he had that made for Big Bang," Cuoco continued. "Steve and I have always had a really sweet relationship and it's just something that we both love so much."
Cuoco said she has been looking at that painting for "12 years," adding, "It's always in my eye line from where I sit in the living room set, so I'm glad I'm going to put it in my own living room, so I'll see it forever."
When asked if she plans on taking anything else, Cuoco said that was it since many other members of the Big Bang Theory family want to take other pieces.
"I've already marked that one," Cuoco continued. "But that one, it looks super random and weird, but it's overly special to me."
Cuoco has played Penny since The Big Bang Theory began in 2007. The show has grown to become the longest-running primetime live-action sitcom in TV history. It was also the most-watched sitcom until last season, when ABC's Roseanne reboot aired.
"The writing, the cast, it all came together and that doesn't always happen," Cuoco said of the show's enduring popularity. "And there's not missing link, and there's not ... it's okay. And there's no, like Chuck said, no one has every half-assed on moment of this show. Everyone cares so, so much. And it means just as much to me as it does to anyone else working here."
Fans have also connected with the characters, who started out as underdogs. Over time, fans have seen the main characters become husbands, wives and parents.
"They're special," Cuoco told PopCulture.com's Huver. "They were the underdogs at the beginning, which now, I actually think they've totally come out on top. They've become cool."
Cuoco continued, "I still think that we made nerdy cool 12 years ago when it wasn't. I think a lot of people thought this was going to be a really silly show with two nerds living next to the hot girl. And we have completely changed that and outgrown that and have become real amazing characters that have left a mark on people's hearts."
The next episode of The Big Bang Theory airs on Thursday, Feb. 14 at 8 p.m. ET.
Additional reporting by Scott Huver.
Photo credit: CBS