Slight Frustration

I am not going to attack anyone on my blog. But I'm a little upset. I'm always nervous to post my ideas for things like NeoVox articles and videos because I'm worried that people will use my ideas. As far as podcasts go many people end up talking about the same thing, but because it's in a discussion format it's less likely things will be repeated word for word. I want to point out that on at least 2 specific occasions during this semester people have used an idea of mine (that I made public far in advance) and ended up saying basically the same thing's that I've said. I'd like to think it's pure coincidence, or even that someone thinks it's a great idea and they would also like to explore it, but I know if it were me I would probably tell that person that I like their idea and wanted to use it or at least mention their name in why I had the idea in the first place. I know this is not just a problem in an online class because I've had it happen in another class as well, but it was more along the lines of straight up plagiarism. I'm wondering is there some sort of online etiquette for an online class about sharing and using ideas or comments? I understand most of it is fair game, but as the typed word becomes the main medium for writers how will we keep track of ideas and give credit where it's due?