[detaro]

Some sites do that (wikis being a common example), I personally never found it all that useful.

What benefit do you see from such an indicator?

[nealrs]

Maybe it's a change in functionality? (new tab vs. new window) or perhaps it affects people's behavior (oh, this is another page on this site - so i won't be leaving / going somewhere else with potentially harmful info)

i don't have a concrete use case yet - but it seems like in a world rife with phishing / bad news / SEO blackhats - knowing if a link is external / internal could be useful.