Wow, so many replies! Thanks at everybody!
The weighing method (which I couldn't find with the search because it never even crossed my mind to browst the clips for the topic ) seems like a pretty good approach which I will definately try, paired with the toothpick idea if only small dots are required.
Did anybody try a syrenge for small amounts of colored lines? I thought it might work, but am not really sure. The icing would really have to be fluid, though... hmmm.
There is a whole category of clips called "Tips, Tutorials and Templates" or something like that. It's where people post images that are also linked to photo tips or tutorials that may be off site. So it's a particularly useful clip set to search for these sorts of things.