While commuting into and out of London throughout much of 2007 and 2008, I became a regular listening of several podcasts. The bug has stayed with me, and I often choose them over television on an evening.
The podcasts being automagically piped down to my MP3 player are (in no particular order)
Buzz Out Loud
FLOSS Weekly
BBC Friday Night Comedy
The Tech Guy
Linux Outlaws
Mac Break Weekly
Net at Night
Tech News Today
This Week in Google
This Week in Tech
Windows Weekly
Over the entire time I have been listening to podcasts, by far my favourite was the LUG Radio Podcast - which unfortunately ceased to exist in 2008. It was easily the most interesting, funniest, and most opinionated podcast of them all - search for it on the net, and enjoy.