Is Mirroring you existing site against googles TOS?

I have two websites, can I mirror eachother?

[kazisdaman2]

I have a website dedicated to engines, and creating another one with a key worded url. Can I use my new site and mirror the existing one, because they are both somewhat related. or is this against the google rules, and other SEO practices?

[g1smd]

If it is an exact copy, or is substantially the same, then you'll get whacked very badly for Duplicate Content [webmasterworld.com].