After some troubles with lots of e-mails with .ppt/.pps attachments I decided to separate them into another mailbox. The first question was: How?
As I use Linux and procmail (www.procmail.org), I searched at google trying to find someone with the same problem and probably with a solution. Many pages after, I found this page (http://hypermail.linklord.com/procmail.old/2001/Sep/0065.html) which has a similar problem and a more radical decision.
Changing just a bit the solution used I got this code that must be inserted in the .procmailrc file:
:0B # slow regexp there's no other way
* ^Content-(Type|Disposition):(.|$[ ])*\.(pps|ppt|mpeg|wmv)
Which I use to redirect all mail with powerpoint and some movies to a special mailbox that I check only when I have time.
I hope this helps other people to do the same and get a better time reading important mail. 😉