I have a stalker. Some weird guy seems to have nothing better to do in his life than pay attention to when I log in to Google Gmail and then instantly hit me up for a chat. If I don't respond, he keeps sending messages. It's creepy. I don't like him. How can I block him from bugging me?

I still have a few old friends who prefer AIM so I use it as one of my instant messenger options (though through Adium, not the dismal AIM application from AOL). Problem is, I sporadically get IM messages from porn site owners and other dopes. Blech! How do I block all of these jerks so the only time I ever hear from AIM is when it's one of my friends?

Not to sound too antisocial, but the new chat feature on Facebook is driving me a bit wacky. Every time I'm on Facebook now, people are bugging me. Is there some way to turn it off?

I'm a big fan of Google's Gmail service, except there are some things I can't quite figure out. For example, some of my mail is routed into folders (well, label bins, whatever they call them) and I find myself paging through thousands of messages to identify those that are unread. Also, can I search through my chat history to find specific things?

I know that Google has quite a bit of reach in the Internet world, but I'm a bit surprised and anxious to see that "Chats" is now a new category in my regular old Gmail account. What's up with that?