Parenting Advice?

I've been playing this ongoing game with my older son.  Every morning when he takes a shower he leaves his boxer shorts on the floor of the bathroom.  This is also the "guest" bathroom, so any visitors who can't hold it have to be subjected to a pair of dirty shorts as they enter the room.  (Sorry about that ladies!)  Anyway, for a while he would leave them on the floor in the morning and I would pick them up each day and put them in his pillow case as a (hilarious) consequence.  The problem is, he didn't really notice - or care.  I figured he took them out each night, but it turns out that he simply moved the lumps around until he found a comfortable position.  I finally broke and removed five pairs of boxers from his pillow case and then yelled, "Why don't you ever just put these in your laundry basket?"  He admitted it was sheer laziness.  Couldn't bother to pick them up off the floor in the morning, and didn't have the energy to take them out of the pillow case at night.  UGH!

I don't know what else to do.  We've started deducting money from his allowance if he forgets, but I'm not convinced that'll do the job.  What do you do when you've exhausted your creative parenting persuasion techniques? You should ask for advice.  So that's what I did... when I was desperate... and nobody was around.  Here's how it went:

Me: How can I get my son to pick up his boxer shorts?
Siri: What is your child's name?
Me: (I don't really see how that's relevant, but whatever) Zack
Siri: OK, I've added this relationship.  I don't have an address for Zack.
Me: Siri, focus.  I just want him to pick up his shorts off the floor.
Siri: I didn't find any places.
Me: He leaves them in the bathroom.
Siri: I didn't find any public toilets.
Me: You gotta pee or something? Come on!  (I figured I'd try another approach) Why are boys so messy?
Siri: Hmm, let me think.  I will search the web.
[Lots of similar questions came up, but with "men" substituted for "boys", leading me to believe this will never change]
Me: I'm sure even you can clean up after yourself Siri.
Siri: Yes.  Now can we get back to work?
Me: Who can give me parenting advice?
Siri: I don't get it.  Do you want me to search the web?
Me: No.  Are you getting angry?
Siri: I can't answer that.  (Wow, so snippy)

I never thought I'd need to consult a computerized voice for parenting advice, but it turns out you get desperate.  And maybe it was the wine goading me on.  I wish Siri had more useful information for me, but maybe boys confound her as well.  I can't ask my friends because we all sit in companionable confusion when it comes to parenting boys, hoping that some important nugget we've instilled will one day "stick".  Really, we are just grooming them for a future spouse.  That's my motivation.  That one day, some girl will not hate me because her husband actually picks up his dirty clothes.  Or at least hides them in his pillowcase. Eh, you can't have everything.