The patent office throws up more questions than it answers, with journalists watching the submissions and approvals in order to root out the latest invention or device coming into production.

Mobile phone patents are a constant theme, but this week a name not usually associated with that industry has been spotted in conjunction with a phone design patent: Nintendo.

The design incorporates not just mobile phone keys but also game controller buttons as well; it was apparently submitted in 2001, but it wasn't granted protection until June 2006.

The device looks extremely retro when compared with today's super-thin phones, but it seems that Nintendo had conceived of a gaming phone before many others.

It's described in the official documentation as "Electronic apparatus having game and telephone functions", but that's about it.

Since it's been floating around for over 5 years now, it seems hardly likely that Nintendo will pull this one out of the wings, but then, maybe it's had its eye on the mobile market and is just biding its time.