Yes, the one I created. I log hours through out the day and when I need to invoice I just select a date range and the invoice is created in PDF format automatically.
I use it locally everyday and it happens to be the app I have applied to YC. It is called PointKit you can see a little preliminary screencast at http://pointkit.com/site
When it is ready to accept Beta testers I will do an official announcement here.
Peldi keeps impressing us with his carefully written and useful articles. I have followed his blog since he released his product and I am convinced he is a great role model for bootstrapped entrepreneurs.
The thing I am most grateful for is that Peldi actually took the time to document the whole process all the way back when he still was working at Adobe and secretly planning to start his own business.
Just go back to his blog and check all the postings from 2008.. a great story. Good work and thanks for sharing how do you do run a great company!
Congrats to the selected ones, can't wait to see what other cool apps come out of this round!