It's funny you say that because we did oklahoma this summer and i did use that very comb. i attached it to the inside of pvc and popped it out of a slit we had cut. good luck!!!!

We made two of them for the show - one that had a six inch wooden spike pop out (for demo) and a 'safe version' that the actors could use.  Took two strudy carboard tubes (one slight smaller than the other) and put  them together like a telescope.  Inside one we mounted a rubber band activated 'spike', with a stopper on the end to keep it from springing entire out of the case.  When you spun the end piece and lined the hole up with the spike, out it pop.  Was very effective, but we had to watch the actors backstage.  For some reason, they were determined to put an eye out with it - hence the 'safe' one for them to play with.  We still have our "Little Wonder " around here somewhere...  took less than a couple of hours to make both of them.

Gosh, I'd have to dig around in the photo archives to see.  We didn't take any 'production' photos when we put it together as it was just sort of a 'what else needs to be done?' moment that inspired it.