The most memorable dialogue exchange in the movie as far as I'm concerned is this:

David Foster Wallace: Yes, you're performing muscular movements with your hand as you're jerking off. But what you're really doing, I think, is you're running a movie in your head. You're having a fantasy relationship with somebody who is not real... strictly to stimulate a neurological response. So as the Internet grows in the next 10, 15 years... and virtual reality pornography becomes a reality, we're gonna have to develop some real machinery inside our guts... to turn off pure, unalloyed pleasure. Or, I don't know about you, I'm gonna have to leave the planet. 'Cause the technology is just gonna get better and better. And it's gonna get easier and easier... and more and more convenient and more and more pleasurable... to sit alone with images on a screen... given to us by people who do not love us but want our money. And that's fine in low doses, but if it's the basic main staple of your diet, you're gonna die. David Lipsky: Well, come on. David Foster Wallace: In a meaningful way, you're going to die.

It's the ultimate irony of technology: It promises connection to others, but can lead to a disconnection to ourselves. Insightful observation from Wallace's character and speaks to one of the story's themes: Connection... or the lack thereof.