I had been searching the web for a few days for a nice demo I saw some time ago.  The demo was open source, and written in action script, and showed many sperm like creatures propelling themselves across the screen with a beautifully animated tail.  I found it again by chance:

http://www.levitated.net/daily/levFlagellum.html

I could not resist making a really quick and dirty port to C++ to play around with this in a way more natural to me.  My horrible source and a video can be seen below.

Source Code:

snakes.cpp

You will unfortunately have to supply your own line drawing function to compile this code, or alternatively you can just used the supplied plot function in my code. The method used to generate the tail movement seems really clever, but a little beyond me without farther analysis. Somehow the movement of the tail is generated only by the first two points of each snake, these movements then propagate down the tail to the tip. It is an interesting an fun looking little demo however.