Credibility of non-journal online publications When publishing in some popular scientific journals, it is easy to understand that it is worth referring to in your CV, job applications, or elsewhere when it is appropriate to talk about your publications.  

But what if your publication is not in some scientific journal known worldwide with 50 years history, but on some online web-site, that is definitely not considered to be very scientific and professional among universities, but at the same time it is quite popular among researchers. I mean it has quite big number of people (tens of thousands daily) using it daily, contains many articles on some kinds of research written by researchers themselves, posting comments pointing out the mistakes, etc.  

Is it worth mentioning or would it be considered not respectful enough place to be published?  

And moreover, what if you "publish" some research on your own blog? Suppose it is popular enough to be considered published paper (i.e., few hundreds or thousands of people have actually read it).

Of course you could ask, "Why not then publish it in the respectable journal?" I would answer that publications I am talking about are not some breaking news or anything, rather just some experiments, that yielded some results, explained couple of things, but not new in any sense, i.e., it is more of educational publications saying "Hey, you can do this and this is how, check it out", probably repeating some experiment done by others, but with more explanations, research, etc. Such publications are not suitable for many journals and I would suspect many journals would not even consider printing it, so it basically can't go further than internet article, though it can get pretty scientific.
One problem with the blog and the website is the quality assurance. A peer-reviewed article guarantees that your research at least meet the quality of that specific journal. Of course some issues exist with the peer-review system but at the moment it is the common way. Everyone can open a blog and popularity does not imply good research. I would suggest submitting the work to a regular journal, and write a shorter blog entry for communication and discussion.