For those of you who already have Gmail and have all those Gmail account invitations and no one to give them to, I call your attention to Gmail Swap. Folks with extra invitations can connect with people who desperately want Gmail and are willing to trade odd and interesting things for them.
I had a couple of invites left, so I connected with a grad student who intends to build artificial kidneys someday, and is just sure that a Gmail account will help that happen more quickly. My second invitation went to a woman who had just got a new kitten. She was looking for names for the cat, which had been found in a dumpster and was covered in oil. I traded her a Gmail invite for the naming rights to the feline, who is now known as Allie, which is short for Allergen. I'm allergic to cats. Really a lot allergic.
Anyway, it's kind of a fun thing to browse through even if you don't have invites left. And if you're one of those folks without Gmail and you still want it, look around for something to swap. It's fun!