Ping of 4000 ms or more, my ping in speedtest is 20

Hi

The first thing I'll admit is that I play League of Legends on a college Internet connection. I know this is not the problem, because I can play World of Warcraft, Starcraft 2, and all my Steam games with no lag to speak of, even with AIM, MSN, Skype, Yahoo, and sometimes Firefox and/or Chrome open in the background.

But even after closing out of every possible extraneous process I can find active and temporarily disabling my Firewall, I still get so much lag playing League of Legends that I'm unable to click anything. That is, my champion won't even move, even after waiting 5-10 seconds for it to happen. I can't buy items, click on my allies or enemies, or even type, but I can watch the game play out.

And this game used to work fine! OTL

Does anyone have wisdom to share?