The cable for our broadband internet comes into the house just under the window ledge, right side.
Somewhere outside our tenth floor apartment (likely on the roof of the building), water penetrates the cable's outermost insulation and is carried INSIDE the cable, into my house, right to the back of my Apple AirPort Extreme. (Wifi base station) I first became aware of this when I saw water pooling around the base of the AirPort. By cutting a small slice in the insulation, we can allow the water to drain before it reaches the base station.
To keep the water under control, we remounted the cable in this u-shaped configuration, with the "drain" at the lowest point. The cable then continues on to the AirPort base station. Do YOU have a drain installed in YOUR internet cable?