I love creating groups in ACT - or for that matter, in any CRM. It's a way of consolidating contacts into meaningful relationships. Examples are christmas lists, prospects, do not call or email, and many others. A client of mine has a "big spender" group - really. You know what that one contains - it's his customers that he wants to ensure get TLC treatment.
As a contact database grows, it is wise to create groups to make accessing the contacts faster. If you have territories or sales reps, a group for each one makes it easy for them to find their data and quickly update the information. Try to remove any hurdles or obstacles from their way. This also removes some of the "gee, I couldn't find the data quickly" excuses.
One trick I've used is to show all contacts that have Public Access set when the database is set to Limited Access. This way, an administrator can quickly find all the contacts that need to be set to limited access.
We use opportunties in ACT and I have a group set for each opportunity stage. In any good CRM, there is a pipeline management system with stages. Create a group for each stage so you can move thru the contacts efficiently and update their status.
Starting with ACT 2005, this became a breeze to set up using Advanced Queries. Set the group once and contacts automatically move in an out without any intervention by the users.
Another thing we do in my own company is to use a Stage field that is a contact versus opportunity field. The stages include Prospect, Waiting on Call, Waiting on Quote, Ready to buy, Ongoing, Lost. I could have had this fall under the ID/Status field but I wanted a distinct field to track the status of the client. And, yes, we keep our Lost customers in our database as well - we have had many come back to us years later. It's pretty amazing how many.
Setting up groups is so easy it's a no-brainer that you shouldn't be missing this chance to streamline finding contacts in your database.
Remember, work smarter, not harder.