Oroboros

According to Wikipedia,

an Oroboros is an ancient symbol depicting a snake or dragon eating its own tail.

This excellent Flash game has you moving an Oroboros using the mouse, and you can eat up little power things, while avoiding them hitting your tail. You can retract your tail for a certain period, as well as acquire a wide variety of power-ups and abilities like electric bolts, or tail extensions.

The graphics are quite pleasant and I recommend going into the game’s options and setting quality to 2x and particles to100%.