With all of this talk recently of the Mac Defender malware and more and more email scams popping up there is a small but simple thing you can do within Safari on the Mac that could prevent you navigating to a dodgy site, and that is to activate the Status bar. This will basically show you the real link you are going to when a link is displayed on a page.
To activate this its very simple, load Safari go to View and select show Status Bar.
Once this is activated, if you hold your mouse over a link at the bottom of the screen you will then be able to see where the link is going, so you can be sure it is a valid url, i.e it may say Halifax Login Page but the actual link will not be going to halifax.co.uk.
This will also work in Mail.app, hover over the link and it will display where the link is actually going.
I am always interested in feedback so feel free to add any comments, or you can mail me here, also if you would like to submit a quick tip with full credit and links back to your site then also feel free to contact me.