With the exception of running through Serial, I primarily listen to comedy ones. My favorites:
Listen to every episode:
Harmontown - Dan Harmon (creator of community) does a weekly live show with friends/guests
Nerd Poker - Brian Posehn and friends playing Dungeons and Dragons (not a huge fan of playing D&D myself, but it's very enjoyable when you listen to comedians play)
Listen when the topic/guest interests me:
You Made it Weird - Pretty much the same format as WTF, but hosted by Pete Holmes.
How Did This Get Made - comedians reviewing bad movies
WTF
The Indoor Kids
This Feels Terrible