How to create a unique identifier for tracking?

Is there an invoicing program that works well with Harvest's time tracking?

• Do you use Harvest for time tracking and another program for invoicing clients? How do you do it? I'm deciding between Freshbooks, Cashboard and Harvest for time tracking and billing clients. So far I'm liking Harvest's time tracking the best, but it doesn't have invoicing included. I would like to have a way to export my data from Harvest into a separate billing program, so that I don't have to create my invoices by hand. There seem to be lots of sites that do billing: is there one out there that can do this easily? The only program mentioned on the Harvest site is Quickbooks, which I don't really want to use. I'm still considering Freshbooks and Cashboard, so if you really love one of those I'd like to hear about that, too. Thanks!

• Answer:

  I recommend http://www.myintervals.com. We developed it to handle the basic workflow of a small web development shop or freelancer. It does task and time tracking, along with billing and reporting, under one application. We found it a lot easier to use one program for time tracking and invoicing, then to use a different program for each.