Google Analytics

This is by far the tool we use- and appreciate- the most. Once you have a website you must know who is visiting your site. You got to know if all your SEO work is doing its job well. You can view the who, what, when and where of all the hits to your site. With this knowledge you can fine-tune your SEO to target directly to your clientele.

Google Documents & Spreadsheets

Or next favorite and heavily used is "Docs n' Spreads" as we call it. This is very similar to Microsoft Office in that you create and edit documents, spreadsheets and PowerPoint-like presentations online. You may download and print everything, but the best point is its sharing capabilities. Once you create a spreadsheet of, for example, your company's price list you can share it with your sales force. They will be able to view the sheet anywhere as long as they have an internet connection. You may even give the viewers permission to edit so you can make it a collaborative effort.

Google Calendar

If you have a calendar in your office Google Calendar is a neccessity. Even more so if you share said calendar with others. Like Docs n' Spreads above this calendar can be shared with varying degrees of permissions. You may even make your calendar public! One example of its use is employee scheduling. You can create the schedule and allow all of your employees to view it from home.

Gmail

Having a gmail account is not neccessarily needed, but it does make things a heckuva lot easier when using Google tools. You may use the same username and password for virtually all of Google's online services and tools. Plus you have a free email address!

Google Voice

Confidentially we are still on the fence about this one. It is still a new service for Google, yet it promises to be very powerful. We are still testing it ourselves. It allows you to set up a new free phone number with any area code and directed to any phone- or phones- you wish. For example, I have the number above directed to a Skype number and my cell phone. When a call comes in it rings both simultaneously. All I have to do is answer one. When connected, it gives me some options: answer, send to voice mail or send to voicemail and listen to the message live!

So far, there has been some mild issues with it, yet I highly recommend trying it out!

iGoogle

This is another worth mentioning. Many people have an RSS or Feed Reader of some kind. iGoogle does it well. When setup you can categorize all of your feeds into easy to access tabs. You can also install widgets to help expedite your daily routine of checking your favorite blogs, checking you emal and checking local weather and much, much more. You will find it makes your day a touch more productive. I even have it set as my homepage just to make it even easier!