My kids love going online and all they seem to worry about is how much computer time they are going to get... drives me crazy (but it is great leverage!). They have their favourite sites they go to but sometimes it's good to shake it up a bit.
A friend passed on this link to this wonderful film for computer by Vincent Morisset.
Animated film meets picture book and you participate in the story. Interacting through each chapter - all my kids had fun with it.http://blabla.nfb.ca/
Storybird - collaborative storytelling
Some oldies but goodies:
Stratch | Imagine, program, share
Flipbook | Create your own flipbook animation
Orisinal | Games created by Ferry Halim
Fluxtime Studios | Create your own animation
Online Kids Zones at Galleries