OK - doodacky is technically a colloquial 'placeholder' name.
See: http://en.wikipedia.org/wiki/Placeholder_name
for a full list of colloquial placeholders.
My wife grew up in Australia, and we've found it in use there - subliminally that's probably where she picked it up - although I have rarely heard her use it before.
We've also tracked it down to NZ and NW England.
What works for me is that the name has no 'inherent' meaning and has a memorable 'ring' to it. So through familiarity it can be associated to the activity on www.doodacky.com. of which more later......