Lenovo’s IdeaPad is an interesting little device – it functions as a Windows laptop computer, but its screen detaches to operate as a stand-alone tablet. While Apple has no equivalent system of its own, a few companies have come out with products that come close. One of the latest is the Notebook Case for iPad, which consists of a keyboard-equipped hinged shell, that accepts an iPad 2 as its screen.

The case incorporates USB and mini-USB ports, and communicates with the tablet via Bluetooth. Unlike some other keyboard cases, it also features a lithium-polymer battery that allows the user’s docked iPad to charge while in use.

Japanese retailer Rakuten is currently offering the case on its website for ¥5,980, or about US$74. There’s no word on availability or pricing outside of Japan, or if it will work with the latest model of iPad. Users who like the general idea behind it, however, might also want to check out the Logitech Keyboard Case for the iPad 2.

Source: Rakuten via 9 to 5 Mac