My Dad and I memorise songs as we wash dishes....we're trying to rig up a music stand in front of the sink right now so we can prop up the verses to "johnny i hardly knew ya". Myself, I tend to find myself humming tunes at inconvenient times....in class or at work for example. That's when I pull out my scribble book and write the lyrics out as I subvocalise. After about the fifth time doing that I've got it down.
Ceit