FreshBooks

I track my time. I bill for my time. I work a lot of different places. I need a way to keep track of it all. Freshbooks does this.

For those of us who track multiple clients and multiple tasks for each client, prepare quotes, and generally have to keep a very tight reign on what is potentially a mess of paperwork, Freshbooks is a godsend. It's very simple to set up, and you have the option of emailing (a small number of clients for free) or snail-mailing (a nominal fee) invoices. The clients can then view them online or download pdfs. A timer lets you precisely how long you spend on each task, and you can prepare a variety of reports to track what's going on. This means that if an invoice is disputed or a line-item is questioned, you can easily go back to see any task or day's specific history. The client can make comments directly on the relevant invoice, and you can track and respond. You can also prepare quotes and compare them with actual work performed.

I find Freshbooks indispensable.

http://www.freshbooks.com/