We didn't even make it to an YCF interview for https://Userify.com (cloud and on-site user/sudo/SSH key management), but we're now profitable with about 800 companies on six continents. (SSH is used on nearly every Linux server in the world for remote management, so it's a pretty huge market; our tool really comes into its own in a more complex cloud environment, since until you get to a certain size you can get along fairly well with just automating user accounts w/ chef or puppet or by hand.)

We're just getting warmed up. We're increasing investment in our agent (for example, we're developing a Windows Powershell version for when Microsoft releases SSH for Windows later this year, so we'll be cross platform.) We're also announcing our first six enterprise customers as soon as we get approval from their legal departments. Some of our new innovations we're still in the process of filing patents on, so can't discuss, but they're awesome :)

We've decided to not take any seed money at all and just self-fund. We've reached 'ramen profitability', as YC recommends, and now we control our own destiny (although we might pursue a growth round later.)

We were rejected in the very first stage (via email) with no reason given. Even if you get rejected: if you believe in your idea, keep going! Success is driven more by determination and persistence than anything else. Something the size of YC is driven by numbers and just one small issue can tip the balance away from you, so by definition they have to pass on a lot of good ideas. Just go for it.