Floating images left/right in an article is no doubt a very common use-case and one I have extended my internal implementation to accommodate. I find the most usable approach that has worked has been to pad the image caption with spaces:
[I am not float](http://foo.com/bar.png) [ I am right floated](http://foo.com/bar.png) [I am left floated ](http://foo.com/bar.png) [ I am centered ](http://foo.com/bar.png)
I could not find a more intuitive and less intrusive way of aligning images. The other proposed ideas I have seen seem unwieldy. This particular solution also doesn’t get in the way of pure text readability.