What you want is a Cable Card tuner for digital cable Your choices are; Ceton InfiniTV 4 PCI express- 4 tuners, internal pci express card Ceton InfiniTV 4 USB - 4 tuners, external box, connects by USB cable SiliconDust HDHomeRun Prime - 3 tuners, external box, connects to your ethernet network Hauppauge WinTV-DCR-2650 - 2 tuners, external box, connects by USB cable You will also need Windows 7 (You can use Linux with the HDHomeRun Prime, but only for channels that are not copy protected by Comcast) With a PC running Windows 7, Windows Media Center (which is included with windows 7), one of the cable card tuners above, & a free cable card from Comcast you can DVR all your recordings on your PC. Which means you can ditch the DVR box from Comcast and the box rental fees. The cable card is free and has no rental fees by FCC mandate. You will also get the benefit of being able to DVR/watch multiple shows at once. And in HD.