P.S.: The best dialogue of this episode (or in fact many many others)
Penny: He came into the restaurant. Sorry the napkin’s dirty; he wiped his mouth with it
Sheldon: I possess the DNA of Leonard Nimoy
Penny: Ya, Ya, I guess. But look he’s signed it.
Sheldon: Do you realise what this means? All I need is a healthy ovum and I can grow my own Leonard Nimoy.
[I mean, WOW... Where does someone get an idea that geeky!!!]
Penny: Ok. All I’m giving you is the napkin, Sheldon