I've haven't fully explored this Flash game yet, but I thought I'd share it with the group anyway...
http://www.crazygames.com/game/flowSo far all I've figured out that you're supposed to "eat" everything you see - including other critters that look like you. (which cracks me up as I'd written in an earlier post that I felt squeamish about the electrocuted cat in the Machinarium sample animation JD provided... I guess that means that single-cell organisms getting killed doesn't bother me as much as mammals getting zapped does
)
The other "pointer" I can give you is that if you press your mouse-key, you go faster.
Lastly, the soundtrack is dreamy. I like it.