i have had my 12" pb for about 6 months now and never have i had this problem. What happens is that during routine web surfing/msn chatting the dock/browser will freeze for a while then suddenly come back. I only have 512mb of ram but i am only running one or two windows plus msn messenger, its not an extensive load. It is really driving me up the wall because sometimes it stalls for 5 minutes before running normally again. Do macs have a defrag like pc's do?