Is there a website that returns 500 (and other) HTTP response codes for testing?

Here is a site that can return any status code:

http://the-internet.herokuapp.com/status_codes

In case you can't easily change the path, but can configure the host easily: http://218.returnco.de/whatever and http://returnco.de:218/whatever

(Disclosure: I run this small service)

I believe http://httpstat.us/ can do that as well.