I have to admit that I have used noreply@mydomain.com for years in cases where I have to give an E-Mail but don't really care about replies. I think I got the idea from GitHub. Before they had the current system with @github.com email addresses I think they recommended to just put a noreply@somedomain.tld in your commits.

When I started I had the intention to just kill the address when I ever will get too much SPAM, but surprisingly this never happened. I think most SPAM bots just filter out all noreply@... addresses.