mattbell

It would be possible to have ads interactively pop up as you're writing an email.  Semantic analysis of your email-in-progress is difficult but not outside the realm of Google's capabilities.  So theoretically it should be possible to get a sense of where your email is going and start serving highly targeted ads that will make the email better, or at least more commercially lucrative for somebody.  The ads could be mixed with targeted search results relevant to what you're typing so that it feels more valuable to the user as opposed to a pure commercial play.  Like many of the other things google and facebook are doing these days, it could come off as several shades of creepy, but past experiences have shown that people quickly get used to these interactions.

So imagine...

- You're writing an apologetic email, and ads for gifts the email's recipient might specifically like start popping up (before you think it's an intrusion by google to share someone else's private info, ask yourself if you have a public blog or facebook account where this info could be gleaned)
- A friend asks you for advice, and as you're answering, links relevant to your answer (some determined useful by pagerank, some placed ads) pop up offering supporting documentation
- A frustrated email to customer support that you're writing starts popping up other people's experiences with the product that are similar to your own, as well as discount sites for replacement parts.