vase? urn? chalice?

and how do they affix to the cake?

There is a great tutorial on making these in Margaret Braun's "Cakewalk".  

Thanks alot!

I saw a dem on them a couple of years ago , they were based on styrofoam balls and PVC pipe. then covered and decorated. They cut they styro balls in half to use as the base and bowl of the piece and connected them with the pvc pipe. 

oh wow thanks!