Hi,
my approach has been to write a sort of "proxy" that expose the alfresco content.
Let's say that the image is located in
Company Home -> resources -> images
I wrote a servlet that intercepts all the requesto to, say, /resources/ and takes the rest of the URL (via the pathInfo) as the "address" of the resource inside alfresco; it then retrieves the image via the web services api and copies it back to the client.
In this way if I want to display the image inside the jsp (or in an html, that is) I just need to write a link of this type:
<img src="/resources/images/myimage" />
As an added feature I use OSCache to cache my contents in order to avuoid calling alfresco for each request.
I hope this answers your question, let me know if you need more details or some code to play with.
Regards,
Fabio