Penny brings in Chinese for the guys and hangs out in her sweats. Don't worry, for now Wolowitz still thinks she looks ravishing. It's only when the new neighbor shows up does Penny need to step it up.
Wolowitz [to Penny in sweats]: Penny, Let me take this opportunity to point out that you are looking particularly ravishing today. Penny: Not with a thousand condoms, Howard. Wolowitz: So there is a number?