Raspberry Pi is a rather compact -- credit-card sized -- computer that packs quite a punch despite being just $25. In this small cheap package lies a computer that:
Other than that, being a computer a number of devices, such as a keyboard, mouse, webcam, mic etc can be added via USB. Another model featuring 256MB RAM and an ethernet port is available for just $10 more -- for $35.
Note that you cannot run Windows on it, since it is an ARM-based computer, however Raspberry Pi will support a number of Linux distros, which can be run off the an SD card. It is unlikely Windows 8 for ARM will run on it either, considering the specifications of the device. Additionally, you cannot run Windows applications on it via Wine, since Wine is not an emulator but a compatibility layer, and Windows applications are compiled for x86 / x86_64.
Raspberry Pi is a great educational tool and a very cheap way to get into computers. Raspberry Pi will be available worldwide when it launches next month, however the shipping costs to India might just take away a bit from its low-price charm.