Hula Hippos, designed by Heinz Meister and published by both Gamewright (and HABA as Maus nach Haus), is a simple dexterity game four players, ages 5 and up.
The components are excellent--a polished wood ring around 4 inches in diameter, and 24 wooden hippo tokens in four colors. The ring and hippos have a nice feel and weight to them, and are smooth, so there is little risk to the playing surface (such as a wooden dining table).
The game is simple; you spin the wooden ring, and everyone attempts to flick their hippos such that they are either enclosed by or under the ring when it stops spinning. Any that meet this criteria are removed from the game, and the ring is spun again to begin a new round. Once someone has successfully flicked three of their hippos into/under the ring, that person wins.
While a simple quick game, taking only 5-10 minutes to complete a game, the experience is fast and fun, and begs to be played again immediately. The hippo tokens slide across the table and bump each other, players shouting, and as the ring falls, there are always a last few desparate shots to get under the ring or remove another player's hippo. Add the zero set-up time, and this makes for an excellent quick filler that will likely get much play.