Do
Let your guests know if they should bring something, and offer suggestions of what would be welcome.

Don't
Ask someone why they're leaving, no matter what time it is.

Do
Show up with at least a little something—a bottle of wine, a box of chocolates or flowers.

Don't
Get drunk and make out in the kitchen, in the bathroom or on top of the coats.

When we received our first invitation from Pingg.com, we responded quickly. Not just because the RSVP was right there in our e-mail. But because we wanted to go to any party being thrown by someone with the taste to have such a well-designed and thought-out electronic invitation. When we got a text-message reminder with the address a day before the party, we decided to bring an extra bottle of wine. So if you need to corral your friends, don't rely on that dinosaur E-vite (which has been pushing those same bits of clip art since '98). And if you feel like your invite's been tossed into a bulk folder, you can upgrade to their surroundSend™ feature which shoots your guests a printed invitation, an e-mail, a mobile text and links to an event page in Facebook. Of course, there is something to be said for looking too desperate. Free, at Pingg.com