This little guy is your friend. Use him. He is at the lower right-hand corner of every single post.
When you see spam or a member being offensive, please use that button to report the offending person.
Why use the report button?
When you hit that button, and enter a small message in the box and hit submit, every single admin and moderator gets notified something needs attention. This is great because if one of us cannot be online, we know someone else will nail the spammer or other offensive post fairly fast.
Case in point: We had a Russian Spammer today. A member sent me a PM to report it. The problem is I cannot be logging into the forum from work, work monitors our net usage and we can get into trouble if we are doing to many things at work not related to work (And in the defense of the member who sent me a PM, I had forgotten to log out at home this morning, so they probably thought I was online...).
In using the report button, the spammer would have been addressed faster. I did quickly log in from work on my lunch and found that someone had recently nailed the spammer within minutes of my log in. However it was a good two hours from the time I got the email that I had a PM, to the time I was able to log in. A lot can happen in two hours - more spam, people unknowingly downloading viruses etc.
So please, use the Report Button. It's your friend. It's that warm soup on a cold night. It's your favorite blanket when the monsters under your bed are lurking.