What happens when a mobile phone company makes a netbook? You get a “mini-laptop” that’s connected to the brink. (The epically failed Palm Foleo notwithstanding, of course.)

Nokia’s Booklet 3G has (duh) 3G HSPA connectivity, a SIM card slot, and WiFi. Its super-thin 0.8-inch-thick, aluminum-encased body houses an Intel Atom processor, an HDMI-out port, and an SD card reader.

The 10-inch Booklet comes loaded with Nokia’s own Ovi software, which includes maps for assisted-GPS, access to the company’s music store, and wireless syncing with a Nokia handset. Nokia claims 12 hours of battery life.

Currently, no pricing information is available, but a connected device like this is likely to be mightily carrier-subsidized. We’ll know more details after the Nokia World conference in September.