Hi Sharky,

You could try "adding" and "subtracting" simple shapes together to get your shape.
The process could be done with the more accurate shape that Michael has made above, where the middle crease remains level.
But this is a quick one example...



1) Draw the outside shape of the cup.
2) Use Revolve to create an egg shape.
3) Draw one straight line in a side view and do a Boolean Trim to cut the egg in half.
4) Delete the top egg half and copy the shape to one side.
5) Boolean Union the two halves together. Delete the flat side objects, as in mine it looked like one overlapped the other.
6) Select the outer curves that make up the flat side, Planar them to get a nice flat area and Join that to the double egg half shape.
7) Do the same thing to make a smaller double egg, Union them together.
8) Boolean Trim the smaller double egg from your larger part.
9) Draw that funny cut-out shape, copy it and Boolean Trim them from the new hollowed out shape.
10) Add the rest to make the tool shape. The the rest will be a series of Copy Rotations and etc.

Hoped this helped also.

Mike