Most newer cases are going to have filters around the fans and you can easily set up a filter for each new fan you install, too. Plus dust doesn't really matter as long as you clean out your case every once in a while.
I'm curious as to why you say don't vent the case too much or run too many fans. Never in my life of working on computers have I heard of that being a bad thing and never have I noticed any kind of negative effects from running extra fans.
gotta be set up correctly. overpressure, not enough vents for all the air to enter/exit, etc..
I think this might be in the right location, but do you guys use internet explorer or mozilla? Mozilla slows down and can't get the the things to download from the electrical section. IE is basically same way, thanks for any advice in advance Mark.