Punchbowl - A party planning and greeting card website
RSVPify - A powerful and awesomely customizable platform for selling tickets online for your event.
BeingSo - Send free animated greeting cards, birthday invitations.
Online-RSVP.com - Beautiful online RSVP for wedding & other events. Create an online invitation, track your guests responses.
RSVP Keeper - Online RSVP's made easy
Whoozin.com - Free RSVP Online | Track RSVP’s and Sell Tickets for your events and recurring meetings.