Two easy-to-follow guides.
Rapid7, the company that owns Metasploit, dropped by the lab yesterday to demonstrate some of its impressive products.
This prompts me to list two excellent sources of information on how to actually use Metasploit. For those new to the software, you could do much worse than read the free Metasploit Unleashed online tutorials at Offensive Security.
Additionally, the book entitled Metasploit: The Penetration Tester's Guide provides similar (but more detailed) information. It weighs more than my laptop, but that's a small price to pay!