Filtering Spam in Foreign Languages
I can't speak for anyone outside the US, but here, we tend to get a lot of spam written exclusively in Chinese, Japanese, and Russian. Outlook seems to block this stuff pretty well, but we're using a web-based mail service (so that spam doesn't get to our server), which forwards mail as necessary (or people use POP3 to pick it up from our email host). In any case, way too much foreign spam gets to the server, which adds time to the download, and is just plain irritating. I don't mean to be xenophobic, but any email that isn't written using a character set I can interpret is spam, as far as I'm concerned.
After some research, we found a way to block much of the spam. This will only work for you if your email host allows you to create filtering rules based on any text within the email. In our case, I added rules that sent mail to the Spam folder if the following text appeared anywhere in the email:
charset="GB2312"
I repeated, creating rules for the following character sets, as well:
charset="koi8-r"
charset="iso-2022-jp"
I'm sure there are others I'll need to block over time, but so far, this method has worked 100% effectively. The flow of Russian spam reaching my inbox has halted, finally.