customer service
If your business has a few departments like sales, customer support, technical support then you can create your gmail email addresses to take care of these issues, you can create sales.myproduct@gmail.com , cs.myproduct@gmail.com, techsupport.myproduct@gmail.com . This is not revolutionary stuff and some may already know about it, but for those that didn't here it is.
If this might seem like a little too much work, then outsource it and have someone handle your emails for you.
Cheers,
Magic
" You can either give a man a fish and feed him for a day OR teach him how to catch a fish and it will feed him for a lifetime"