Being that we are soooo (im)mature, here is a selection of words for you that will pretty much make us giggle at any given time, regardless of their context:
crack
pole
wood
bone
bung
poop
log
Heh heh, you said "log." Sometimes you just have to be inside our heads to truly get it. Oh, and that reminds me:
head
We will continue to add to this list as time goes on. Feel free to share words that make you laugh. :)