If you are looking at a nettop that is compact and is also not too expensive, here is something you could look at. Asus is launching a new Eee Box EB1501P nettop that comes with a pretty neat and compact form factor besides offering some decent specs. The device is expected to launch in the USA market in a few weeks from now.
From what I hear, the Asus Eee Box EB1501P nettop will come with a dual-core Intel Atom D525 processor that is backed by a powerful NVIDIA Ion graphics chipset for graphics processing. The hardware specs include a 4GB DDR3 RAM, a 320GB hard drive storage and ports for USB, HDMI, eSATA and ethernet connectivity. The device supports Wi-Fi 802.11b/g/n connectivity and if the immediate release will include a DVD burner, though later releases (September launches) could include a full-HD Blu-Ray drive. The Asus nettop shall be a Windows 7 Home Premium machine.
Speaking of price, you could be spending close to $500 for all these features detailed above. If high definition gaming is not what you are looking at, this is a good nettop to consider.