Thing #18 Online Productivity Tools

I checked out Google Docs because I know of several people who regularly use this tool...I am biased toward Microsoft Office because I feel comfortable using these tools. I noticed Google Docs was similar to Word, the thing I missed most was instant spell check. I have been told that people who use Docs often type in Word and then paste into Docs. It was fairly easy to do a spell check at the end of typing; I would just need to remember to use that feature. I liked the collabortive aspect of Docs, sharing was easy with the email option, making comments was just a click away. I wonder though if all these tools overlap, since you can get the same type of features in a Wiki.
If time allows I may explore Google Docs some more, but until then my needs are met with Microsoft Office package.