Best Quickbooks alternative for invoicing?

I don't use 90% of QB capabilities. I only use it for invoicing and tracking who owes me how much. That's it. No payroll, no banking, nothing else.

Now that they won't let me send emails from QB without signing into my account, but won't actually let me sign into my account, I can't even email invoices out, so I'm done with their crap.

What's good for simple invoicing and tracking?