Junk Mail filter for POP3 email

Anyone know of a good way to filter spam out of pop3 mail. My parents account gets tons, and they dont check it too often so it ends up getting up to 200 - 300 messages before they check. Any ideas on how to keep it under control.

there are many hits frome Google about spam filters.

Try this first though

Most of the links I found on a Google search point to third party software you install to filter out the spam.

Iv tried that, doesnt seem to work well / at all. I was actually kinda looking for a program to filter it, and im wondering if anyone has any sugestions.

I got it working. Before i was using the do not download from server command, and it didnt to squat. Using the deleat it command and a few key words and phrases (such as "the word remove in the subject" and "to be removed click here") HEHE, play them at there own game. Iv got it so that it blocks about 90% of junk mail, which is pretty dang good.