Take one part Super Mario Bros., one part Kirby, and just a dash of Pac-Man, and you'll get Hoggy, an iPhone app that combines familiar elements from many console classics. In Hoggy, you control a Kirby-like character (named Hoggy) in a 2-D side-scrolling game. The levels/artwork look similar to Super Mario Bros., especially in the opening screens. Many levels take place below ground, as you enter different jars. Again, a familiar concept from the Mario franchise.
What is unique to Hoggy is the control scheme. Hoggy moves by jumping and sticking to the roofs of the different levels, then a tap drops Hoggy into place. Leaning the iPhone/iPod moves Hoggy left or right. The whole thing plays as a fun mashup of many games you've seen before, but the controls might make them better for the iPhone than the original.
There's a lite version with several included levels that will give you a great (and free) feel for the game.
Here's a look: