If you are a small business owner who wants to make your invoicing easier to create, send and track, Freshbooks is probably the coolest and easiest to use on the market today. You can sign up for a free account (up to 3 client) to give it a try. When you sign up you get your own business URL (example: http://yourcompany.freshbooks.com) which is customized with your company colors and logo. You can also track expenses and keep track of your time while working on a project.
To learn more about this amazing little software program, check out Freshbooks. One final thing that I personally like is how Freshbooks integrates with a number of other quality online programs such as: Outright.com, Clarity Accounting, iPhone, etc. For a list of the programs Freshbooks integrates with: Check the Add-On list.