Orange soda.
With my third baby, she did not want to come out (in stark contrast to her sisters, who all seemed to want to give me about one hour of advance notice before getting born) and the midwife said, before trying induction, try castor oil, sometimes it will kick the labor on. Not a spoonful, no. A whole bunch. And don't puke it out. I chased it with orange soda because I liked it but figured I could certainly manage without it.
Oh God. I couldn't even look at orange soda without nausea for several years. And it didn't even work, I still had to get induced!