Update: The plugin now has a simply but hopefully very effective protection against automated spam bots.
Install, add [zcmail] on some page or post, done.
Shortcode demo, please don't send me test mails:
Downloads at WordPress.org.
Since 0.3.1 the plugin includes a CSS file that is included by default. If you want to modify the CSS styles please have a look at:
WordPress plugin demos are disabled as I don't use WordPress on this site any more.