Full cream so you can get the nice 'creamy' effect!
Joe, the process was as follows.
1. Eliminate ambient light
2. Set camera to Manual mode and aperture to around f/22.
3. Lock shutter open using cable release.
4. With flash positioned to the side use one hand to drop the milk (i used a plastic cup with a small hold in the middle of it full of milk).
5. Use the other hand to fire the flash as the milk hits the saucer.
6. Put the cup down and close the shutter.
Then repeat till you get the right pic 
I had to drop the output on the flash to about 1/2 and also use the wide angle pull out. You can use a combination of a smaller aperture and the flash to control exposure.
Hope that helps.
Of course having an assistant with good relfexes will help too.
If you want to try something interesting you can also try a multiple exposure. For this, just set the flash output to half the normal exposure (so in this case 1/4) and then you can take 2 shots of two different drops of milk. You'll get some interesting effects!