Of course in Italian
slang, "ditalini" is the plural of
"ditalino", meaning "female
masturbatory act".
I would safely bet this second usage vastly outnumbers the pasta one.
The reason for these seemingly wildly different meanings is to be found in the stem word "dito" == finger. Hence
"ditale" == thimble and "ditalino"=small thimble. I don't think I have to explain further on the second meaning...