Maybe Signs101 got hacked? I am not seeing any ads on my computer and I have AdBlock Plus turned off.
I AM however getting a notice about this website trying to load scrips from unauthenticated sources and Chrome is blocking it. Maybe that's what all the fuss is over?
If it's coming from the ads, then the vector is more then likely coming from the server that hosts those ads. Which is why I have a problem with 3rd party anything on a site. While the site itself may be secure, doesn't mean that 3rd party server can't be a problem.
I'm willing to bet S101 has a virus or got hacked...the behavior of those ads look scammy to me.
Ya'll try using Chrome, it's a million times safer than IE's crap