It's possible to put your work on any of the sites David mentioned but then you have to figure out a way to compile them into something somebody's going to be able to view. LinkedIn has the ability to add projects to your profile but I think in the end your own website with a portfolio is the best option.
When I share a link with the community I usually share the link to either a blog post with the project and information on it or to it on my portfolio, depends if I deem the project I did good enough (portfolio) or if it's a work in progress (blog).
I'm an advocate for having a portfolio and I love having mine around, it gives me a good place to show all my favorite work and I can put anything on there.
Recently I've been writing a lot about the benefits or having a portfolio, and blog which I also love dearly :-) (http://www.nickleffler.com/blog/)
Also created a course how to set up a portfolio (and blog) website similar to mine (technkl.com). More info on that here:
http://www.nickleffler.com/courses/build-online-portfolio-blog/