Sorry, TiVo isn't available yet in Ireland. In the US it's killing advertising. It allows you to record shows from your cable and watch them whenever you want. Better than that, you can watch other shows while it is recording. It stores up to 30 hours at a time (I think). Even if you are watching a show live, if you miss a bit, you can rewind and then watch it time-delayed until the ads come on and you can fast forward back to real time again.
What my mate usually does is set the tv to record the first half of a show, join in in the middle and fast forward each of the ads so it finishes still at roughly the same time as the original. Sounds a bit like fancy video, I know, but so much better.