My project "UrlRoulette" was on the HN homepage for about 24 hours. I received a huge traffic spike at the start. Since then traffic came from other sources such as Reddit, some blog posts and articles that were written - and of course some search engines. After being on HN, UrlRoulette was featured in the german C'T magazine and received a lot of traffic from their website and their print edition. Also, being featured on some more sites certainly helped pushing the site's page rank on Google.

The project: https://urlroulette.net/

I actually wrote a post about being on the HN front page: https://hackernoon.com/urlroulette-24-hours-on-hacker-news-e...