Right, mine, during week days are - 1-2 lessons on my way to university, sometimes I manage to listen for a bit while at university when nothing's going on, then 1-2 lessons on my way back (by 1-2 I mean I usually have time for one, but sometimes, like during traffic I can squeeze in a second one or at least part of one) - on my way back I listen to the same material as when going to university. When at home, when doing creative work or, say, playing NFS I put in older episodes in the background - usually about an hour's worth or so.
Been listening for around a year now (I don't really keep track) - if anyone wants to practice some beginner level japanese my skype is yuriythebest1
Japanesepod101 is epic and fun and a treasure for humanity!! all those courses that you have to travel to and pay thousands of $$ for can