Starting at $450 up to $700, the Acer x1200 is about the size of a large book complete with 4GB of RAM, an AMD Dual-Core processor, up to 500GB in storage, and even an eSATA port to go along with the nine USB ports. While Nvidia has taken some lumps as of late for their mobile GPU issues, this unit has a GeForce 8200 integrated along with two PCIe slots (looks like half-height only).  The Mac Mini has little in terms of performance on this gem if you can spare an extra inch and some cost savings.  I am curious about power consumption and heat though and an HDMI out would seal the deal.