Add prefix to every URL

Hi!

Is there a way to add a prefix to every URL in a WP blog?

Normal posts would look like:
http://www.domain.com/prefix/post-slug

Categories would look like:
http://www.domain.com/prefix/category/category-name

Archives would look like:
http://www.domain.com/prefix/date

And so on…

The obvious solution would be to install WP in a directory named ‘prefix’, but I don’t want to do this.

Any ideas on how to do this via WP API code?

Thanks in advance