I've got an interesting idea on one way to use the RB250GS.
We might use it as an inexpensive "4-port ethernet card" in an x86 MikroTik. Essentially, we would use VLANs between the RB250GS and a VLAN-capable single-port NIC. Obviously this wouldn't be a bright idea if we were pushing a heap of traffic, but you get the idea.
Next, I came up with the idea of somehow mounting the RB250GS board in the rear of a 4U server rackmount or PC tower case and splicing the 12V DC line from a molex/IDE power connector into a DC jack that fits the RB250GS power jack.
Even though the PDF [link], that roc-noc.com posted, says "Jack: 9-28V DC," I'm not sure that 12V would be enough to power it. Any thoughts?