The tiny ASUS AT3N7A-I motherboard is home to an Intel Atom 330 with an active cooling system, not that you are going to get to overclock the Atom; but iXBT Labs warns that you may want to modify it as it is quite noisy.  As well you will find Bluetooth, HDMI, eSATA, 3 x SATA-II (300 MB/s), 10 x USB, a legacy PCI slot and a pair of DIMM slots.  If you are willing to swap out the installed fan, you can have quite a good base for an HTPC.

“The NVIDIA ION platform and Intel Atom processors are getting increasingly popular. Vendors are launching new motherboards, nettops, and netbooks based on the “Ionized Atom”. The reason for such popularity is simple: ION is presently the only option for a supercompact, relatively inexpensive, and potentially noiseless HTPC or an entry-level gaming computer.”

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