Ever since I first got my DSL Internet, I've had this problem with the connection futzing out at random and taking about 20 to 30 seconds (or longer) to reconnect. I wasn't sure if it was the modem or the PC, but now I know for sure it's the modem, because I have twice tonight (since I'm sitting right by it) seen all the lights go on at once and stay there for a moment, accompanied by an odd click noise, before going into the "okay, I'm starting to connect to the Internet now, Boss" light pattern. So for some reason, the modem is just having an aneurysm every now and then at random. Which is very annoying. I had to restart the download of OpenOffice to my new laptop twice before I gave up and switched to the nearby unsecured wireless "Ravnica" network so it could finish.
So yeah, even more reason to switch to cable Internet. Which I've been meaning to do anyway.