Gakked from several people on my friends list:
If there are one or more people on your friends-list who make your world a better place just because they exist and who you would not have met (in real life or not) without the internet, then post this same sentence in your journal.
I'm including e-mail lists - LJ has been a wonderful supplement to them! There are any number of you I wouldn't know as well, or be as close to, without LJ in specific, and the internet in general. And my life would have been much less rich.
Not to mention the fact that I'm an Internet Dating Site success story - I don't see how I would have met my darling wife without the internet!