Hey guys, found some free time, so I thought I contribute to my favorite forum.
How to changing the in-cabin microfilter...and with a slight "mod" for you brave souls.
All pictures were taken with a Canon Powershot G5 digital camera. Someone broke
in to my apartment, and stole the Canon D30. It's ok...Canon 10D is on the way!
As always, do this on your own risk. Altimas.net and I are not responsible for
your screw-ups. Although this is an easy job, and it's in your
owner's manual under section "8-22: Maintenance and do-it-yourself".
You really don't need any tools for this job, maybe a pair of scissors or razors for the "mod".

First you'll need to stop by your friendly neighborhood Nissan Dealer.
You'll need to buy this nice box. The ALL...NEW...2004...
Nissan Genuine parts In-cabin Micro filter box!
But wait! There's more! Inside this box contains...

A hi-tech in cabin micro filter! But wait...there's more!
There's also a free hi-tech sticker, so you can put the date of when you last changed it.
You're probably thinking..."Man! All this will cost at least $60!" No way!
You'll get all this for the low, low price of only $29! But wait! There's more!
If you order now, Nissan will throw in the official "Nissan" word stamped on the side
of this once in a life time collectible filter! Order now! Operators are standing by!
(I'm being sarcastic for those who don't know...I mean dang!!! $29???? It's just
a paper filter!) Any ways, See that red arrow? Yeah, you should stick / glue that
nice metallic tag somewhere, and date it.

Make sure your engine is turned off. You may have to go underneath your glove box to do this,
but I actually just sat in the passenger's seat, and found it without looking.
If you are unsure, just see your owner's manual. The red arrow is pointing to
one of the two pins that is acting as the bottom hinge for the glove box.
You'll need to pull the levers outwards, and gently yank them both out. Make sure you
emptied out all the contents inside your glove box before doing this...trust me on this one.

Here’s a picture of one of the pins, partially pulled out.

Ahhhh...the beautiful hi-tech pins...I'm afraid to ask what's
the price on these babies if I lose them.