From Boing Boing comes a post about a website,, which lets you send an email to yourself (or conceivably, someone else) in the future. Here is the email I sent:

Dear FutureMe,

Worried about the privacy implications of this website, but I guess you would know better. Are you still paranoid about privacy? I hope so. Can't wait till comes about! Anyway, lots of love, and here's hoping you have a flying car.