I've seen a fair number of amusing haikus over the years, but this one had me ROTFLing:
Sleep is for the weak
Caffene is my sacrament
Are those spiders real?
Picked that up at this year's World Science Fiction Convention in Boston, which, BTW, totally ROCKED!
Feel free to add your own favorite amusing haiku here. Spamku highly welcome:
Canned in mystery
Eaten in desperation
Third world currency