I've used those, and they fail for my use cases because you can't put all kinds of stuff in them. Most of my notes and code are textual, but sometimes I have to

I've used those, and they fail for my use cases because you can't put all kinds of stuff in them. Most of my notes and code are textual, but sometimes I have to use rich text and colors and embedded pictures. Sometimes I need to store audio or embed arbitrary attachments in my notes. Things like Notational Velocity can be simpler because what they do is simpler.