I like Google Docs because it allows you to work with other people, and you can see when your writing partners logged on.
I really found the iGoogle startpage interesting because all my tools are in one place.
Blogs were interesting
I liked the google docs a lot because of the collaboration feature built in.
I thought the iSite tool was most useful.
The Google docs with the presentation piece especially is fantastic. Being able to also share it as a .pdf or a .ppt is very useful.