Example: Mockr (https://github.com/causes/mockr-old). A sweet app that lets you share and review designs among teams (and as per last check, it was unmaintained). We ported it to Bushido with a few extra lines of code and it's here https://github.com/HashNuke/mockr
If you have apps like these, that you think others would find useful, mail me ([email protected]) and I'll help you with porting it to Bushido. And if you are using Devise for auth, we have a plugin and it's 5 lines of code promise! Most apps that we've ported, we've ensured that they work fine outside of Bushido too (opensource is giving back. right? :)
And yeah, there are a handful of SaaS products that are open-sourced, but most aren't maintained to a high-enough quality for our tastes. We'll work with developers to up the standard.