I have Verizon FIOS at home and have been considering a device for streaming the cable to my iPad when I travel. Two things come to mind Slingbox and EyeTV from ElGato.
The downside of EyeTV is it can only handle the ClearQAM channels from your cable box, everything else has to come from an off the air antenna. I am not sure if Slingbox has this same restriction. I would be interested in hearing from anybody that has been happy with the streaming device in sending your cable signal to a device like and iPad or smart phone when away from the house via internet or 3G.
Slingbox (HD) requires a component video connection from the cable box. That output is often disabled if you also have an HDMI connection to your TV.
So if your cable box has a component (RGB) output, a slingbox HD PRO is probably your simplest solution. However, it may have to be a dedicated cable box, or you would need to yank the HDMI cable when you plan on being away from home.