Anyone who's ever been on newsgroups knows that there is a lot of spam.  Outlook express doesn't allow you to filter newsgroup messages by words in the body of the message, so you often have to grin and bear it.

If you don't know what I'm talking about then chances are that you don't need this filter.  But people who use Usenet have been complaining for ages that Outlook Express doesn't have this capability.  There are spammers who change their name 20 times a day and the normal Outlook Express filters are ineffective against that.  Anyway, here's the solution. 

You have to be comfortable playing around in your Windows registry.

First, (outlook express), create a normal newsgroup rule, and tell it to filter out
any messages with "XYZ" (or whatever) in the subject line, and
remember what you called the filter, because you'll need to know that name later.

***Note:  Be sure to specify the newsgroup you wish to apply this rule to, as this is the only thing you won't be able to change after.

Then go into your registry and find that new filter, which will be in
HKCU/identities/<your identity>/software/microsoft/Outlook
express/5.0/rules/news.
Once you're there you'll see a bunch of numbered folders, and if you click
on each of them once you can find the one that has the "Name" value that you
assigned to the rule you created.
Open up that folder, then open up the Criteria folder that's inside that. 

Now, inside the Criteria folder will be one or two folders labelled 000 and 001.  If there is only one (000), left-click it once.  If there are two (000) and (001), select the one with the higher number (001).

Double click on the word "type" in the right pane, and change the value data
setting to 9.

Restart your computer, and you have just created an outlook filter that you
can use to filter out newsgroup messages that have certain words within the body of
the message, like "buy now", or whatever.