I downloaded the PDF when I saw it from Slashdot... Apparently LAN devices aren't at risk, it's mainly (but not entirely) 56k-and-below modems. I have a DSL modem here, but I highly doubt it is also at risk, given that it is a multi-state LED (red, amber, green) and when it does flash, it's usually not because of information flowing, but rather the status of the modem in regards to training the DSL link.

At any rate, it's another interesting thing to think about when you make your little cave-of-paranoid-solitude, eh?