It is pretty difficult to locate Comcast channels after they switched over to digital format. So I went through one by one with the TV to try and document them all. These are for San Francisco, California. They may not be the same for other counties like San Mateo, Contra Costa, or others.

If you have any recent model LCD/Plasma TV (at least within the last 3-4 years) with digital tuner, you should be able to tune into the QAM channels. Some of the USB and PC peripheral tuners will also be able to tune into the QAM channels.

I'll update the listing if things change over time but hope this helps. It's a shame Comcast doesn't publish these channels to service listings that allow companies/devices like Tivo take advantage of. They are literally shooting themselves in the foot with these kinds of tactics.

Channel Station
81.11 Nickelodeon
81.2 Oxygen
81.3 Discovery
81.4 TLC
81.5 Comedy Central
81.6 VH1
81.7 Cartoon Network
81.8 Spike
81.9 E!
83.1 Vs
83.12
83.2 Bio
83.3 History International
83.4 Lifetime Movie Network
83.9 Style
86.4 Food Network
86.5 MSNBC
86.6 Disney Channel
86.7 USA
86.9 A&E
94.11 HGTV
100.1 C-SPAN
100.10 QVC
100.12 Headline News
100.2 C-SPAN2
100.3 Animal Planet
100.4 Travel Channel
100.7 CNN
100.8 Golf Channel
100.9 HSN
121.1 Latination
121.10 News Radio
121.11 Classical Radio
121.12 Latin Jazz (KCSM)
121.13 Radio
121.14 Pop Radio
121.15 Spanish Radio
121.16 Contemporary Radio
121.17 Radio
121.18 Pop Radio
121.19 Radio
121.20 Country Radio
121.21 Country Radio
121.22 RnB Radio
121.23 Radio
121.24 Radio
121.25 Classic Rock (KFOX)
121.26 Spanish Radio
121.6 Hispanic (Telemundo?)
81.10 TV Land
86.10 FX
86.11 Lifetime
86.12 AMC
87.13 SyFy
87.14
87.3 Hallmark
87.4 Tru TV
89.1 TV Guide
89.10 SFGTV2
89.11 GOD
89.12 ARTS
89.3 Weather Channel
89.4 Link TV
89.5 Comcast Home
89.6 SFGTV
89.7 ShopNBC
89.8
91.311 MTV
94.10 Bravo
94.14 TV Land Prime
94.9 History
98.11 VH1
98.13 GEMSTV
98.5 FCS
99.13 G4
99.5 Bloomberg
99.8