I'm not a console game collector, so I've noted this fairly late:

Certain companies number the games released for their consoles. I'm not sure if it's called the cartridge number or just catalogue number?

Where to list this info? I didn't get answers from the approver, neither in our MobyStandards. Can we enter this in the release comment field?

I think it's significant, e.g. Western collector of Asian games may find it easier to refer to a title by its number alone and not a confusing translation/transliteration. The numbers are featured on the packaging (i.e. they don't change).

Examples:
http://en.wikipedia.org/wiki/Super_A%27Can
http://www.old-computers.com/MUSEUM/software/casio_pv1000_gpa-109_box.jpg
http://www.mobygames.com/game/odyssey-2/kc-munchkin/cover-art/gameCoverId,150158/

I suppose it's not exactly the same, but we do list the Ps1 -> Ps3 Sony PN numbers, so I can't really see why it couldn't be done on other platforms as well... The Dreamcast is a prime example... or the Saturn.

Popper's already shot down publisher specific release codes. Unless a code/number is universal for every game released on the system it's not going to fly.

Trivia?

Not trivia, more like release info comment.

We have that for NES.

No, it has to be added as "product codes", from the "contribute" page [«Contribute UPC, EAN, ISBN, Sony Part numbers and other product codes for your games»]: although who wrote that judged expedient to only mention Sony, all console games in my ownership (namely: for any Nintendo game system, Dreamcast, Saturn) are given product numbers that univocally identify the game and each release of it. That is helpful for both collectors and database purposes. The code to be taken in consideration is that printed on the media (cd, cartridge, other, ... ) and not in the spine or back cover: these coincide sometimes, but not necessarily.

All of the Nintendo product codes are supported here, just like the Sony ones.

You bet! I was just expressing my disappointment for the fact that, well, this is what is said about product codes in the contribution starting page: «Contribute UPC, EAN, ISBN, Sony Part numbers and other product codes for your games.». And these are the instructions about «packaging» for cover art: «Describes how the product was packaged. Games are released in many different types of packages. PC Games are most commonly shipped in boxes. Dreamcast, and PSX games in jewel cases and Xbox/PS2 games in Keep Cases. Occasionally games are released in other packages.»

One may be afraid that nobody in the site knows about Nintendo game systems; thankfully that is wrong, and it's just that who wrote there regard(s) them as minor... however this really does not suit this site seriousness.

Sega had a consistent part number scheme across every one of their consoles, from the old SG-1000 up through the Dreamcast...in Japan. Every Japanese release on every Sega platform follows this scheme. There was an extension to it for international releases, but it was spotty at best when SOA/SOE actually followed it.

Hell, I think even Sega's arcade games followed this same part number scheme.

But as in the example above, I repeat:

http://www.old-computers.com/MUSEUM/software/casio_pv1000_gpa-109_box.jpg

Where should I put that GPA-109?

In the comment.