I had an opportunity to play with the new Nokia N810 Internet Tablet for about five minutes last night, and came away confused. It seems pretty darn expensive for a machine with limited usefulness. Even the name is misleading -- a "tablet" should be a device the size of a notebook computer; the Nokia N810 is a pocket-sized computer.

Before I go into a bit more detail, I want to emphasize here: This is a first impression. I played with the device for about five minutes, at a Nokia-sponsored reception at the Web 2.0 Summit in San Francisco. It was noisy at the reception, and I was tired. So you should read this post very skeptically.

As my colleague, the doughty Rick Martin, reported, Nokia launched the Nokia N810 yesterday at the Summit. To use the device, you connect over a Wi-Fi network, or a Bluetooth mobile phone.

And that's its main drawback -- you're paying nearly $500 for a device that only connects over Wi-Fi, and you need to spend more money on another smartphone if you want to connect over other wireless networks.

What's the market for this thing? It seems to me like this is a toy for rich geeks -- people who can afford to spend $500 on a whim, the way you or I spontaneously buy a magazine. Once Nokia has sold a N810 to all the entrepreneurs presenting at the Web 2.0 Summit, who else will they sell to?

The N810 runs the maemo Linux based OS2008, a Linux distribution optimized for mobile devices. It has applications to connect with Google Mail, Facebook, or YouTube videos. It supports Skype instant messaging or VoIP, and Gizmo video chat with an integrated VGA camera.

The one application that might prove me wrong: The N810 supports GPS navigation. I paid $800 last year for a Garmin Nuvi GPS system, with very limited MP3-playing and photo-sharing ability (and I'm still hearing about that from my wife). The N810 is a GPS and fully functional pocket computer, for more than $300 less. That's tempting. On the other hand, Nokia's marketing message is confusing -- they want to be all things to all people. Most people who are looking to by a pocket-sized GPS system will overlook the Nokia because they don't know about it.

The device has 10 Gbytes memory for music and video playback.

I found the controls on the device hard to use. It has a slide-out keyboard with tiny little keys -- my short, blunt fingers found them difficult. If you slide the keyboard closed, you can use a tiny, on-screen keyboard that you tap with the unit's built-in stylus, or switch to a larger keyboard that you can tap with your fingers (like on the iPhone). The N810 also supports handwriting recognition, which you have to train, like on the old Apple Newton; without training, I tried to enter 10 letters and the Nokia only recognized one correctly.

A row of hardware buttons on the top of the device, behind the screen, controls functions including zooming the browser in and out. I was unable to get those to work correctly.

I took a look at the InformationWeek home page using the built-in Mozilla-based browser. It looked fine. However, zooming on Web pages is, as far as I could see, vastly inferior to the iPhone. On the iPhone, you tap twice on a column of text or another block of content on a Web page, and the browser automatically zooms so that the block of content fills the width of the screen. On the N810, as far as I can see, you zoom and pan manually to find the block of content you want to examine closely. (And when I say "you," I mean "other people" -- like I said, I was unable to get zooming to work right.)

I applaud Nokia's innovation in coming out with the N810, but it seems to me that it's not ready for the market yet. When they build a cell phone into the thing, with support for 3G and other high-speed wireless networking, I expect they'll find a nice market. People will be willing to trade the relatively clumsy interface for the flexibility of a Linux-based computer. But, until then, the N810 looks to me like an expensive geek toy. As Rick noted: It's like Palm Foleo (announced but never released): An expensive, limited-function device with no clear purpose.