Google has long been trying to convince users that even though Gmail and Google Applications has a beta tag (usually given to software that is not yet ready for prime time) Google Apps is ready for use in corporate environments. The reason why the beta tag has stuck so long? "We've focused our efforts on reaching our high bar for taking products out of beta," explains Google employee Matthew Glotzbach.
Despite wearing the beta tag for more than five years Google can boast a list of credentials typical of enterprise software. Google reports that 1.75 millions companies run their businesses on Google Apps.
KTG uses the free version of Google Apps for just under a year. I think that Google Apps is about the best option for any small business.
Google provides corporate email and a shared calendar. In fact I've heard many users say they prefer Google Calendar to MS Outlook.
If you are interested in learning more about Google Apps click here.
Or you can read Google's Official announcement here.