Introvertster is an online community
that prevents stupid people and friends from harrassing
you online.
You can use Introvertster to:

Avoid invites to chat, filter
out annoying invitations for Meetup, birthday parties,
or after-hours get togethers.

Packet flood a friends Internet
connection making it impossible for them to send you
an instant message.

Help your friends get a clue
that you really don't like people or care for idle chit-chat.
Create your own barrier to protect
yourself against interaction with people. It's easy
and fun!