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.
The guys gather round Leonard as he sits in his time machine which arrive. The time machine is, of course, the prop from the 1960 movie that he bought off ebay.
Sheldon: I'll have a diet Coke. Penny: Can you please order a cocktail? I need to practice mixing drinks. Sheldon: Fine... I'll have a virgin Cuba Libre. Penny: That's... rum and Coke without the rum. Sheldon: Yes, and would you make it diet?