I have a few that I really like:
Car Talk! Car Talk is a radio talk show broadcast weekly on National Public Radio stations throughout the United States and elsewhere. Its subjects are automobiles and repair, and it often takes humorous turns. The hosts of Car Talk are brothers Tom and Ray Magliozzi, also known as Click and Clack, the Tappet Brothers.
http://www.npr.org/rss/podcast.php?id=510208
This American Life. This American Life (TAL) is a weekly hour-long radio program produced by Chicago Public Radio. It is distributed by Public Radio International and is also available as a free weekly podcast. TAL, hosted by Ira Glass, is primarily a journalistic non-fiction program, although it has also featured essays, memoirs, field recordings, short fiction, and found footage. The first episode aired on November 17, 1995.
http://feeds.thisamericanlife.org/talpodcast
SPEED Engine Block.
SPEED's Engine Block delivers the finest muscle machines in all their glory - from inside Barrett-Jackson's auction house to the Detroit stories of American Muscle Car. (I just watched Barrett-Jackson auction a 63 Corvette concept..for $1.6 MILLION!!!)
http://podcasts.speedtv.com/engineblock_podcast.xml
Do you subscribe to any podcasts?