McAfee ShareScan provides a simple way to identify all the connected devices on your network, while displaying information about whatever they might be sharing.
Launch the program and it will automatically detect your network and IP address. Click the Start button (bottom left) to have it check the specified IP address range, and any connected computers will be listed.
You can use the program as a quick network browser, then. If you're not sure about the IP address of your network storage advice, say, or its network name, then ShareScan will quickly reveal all.
And you'll also get a quick indication of what the device is sharing (folders, printers, devices and so on), although this is only a summary: the program can't identify which folders are being shared on a drive, for instance, which is a pity.
McAfee's ShareScan is a configurable and easy-to-use network scanner, and as the program is portable you can copy it to a USB drive and run it anywhere.