Lifehacker - 30-Second DVR Tweak Speeds Up Commercial Skipping - TiVo
http://lifehacker.com/5224637/30+second-dvr-tweak-speeds-up-commercial-skipping

30-second commercial skipping on his Comcast DVR:

interesting comment thread on other dvr's including replay history

DVRs have revolutionized the way people watch TV, but if you've always wished your DVR were a little better at skipping commercials, this classic 30-second skip hack is a must. For what it's worth, we realize that these tricks aren't new by any means. Still, we've never featured them here, and the aim of this post is to collect as many of them as possible. Right now, we're aware of two hacks of this kind: one for the TiVo, the other for Comcast DVR.