www.babygaga.com is a great one for expecting moms. You can connect with others and also get great tickers to display in emails etc.
www.babyzone.com I love this one!!! It has a calendar that tells you what week you are in to the day and then has ALOT of information whether this is your first time around or fifth. You can keep appts. on the calendar and it has a to-do list as well as widgets and lots to do.
www.babycenter.com is another good one somewhat similar to babyzone yet a lil different.
I am always finding new ones and they are keeping me busy LOL 
