Station 38

Pat Kemp is a mainstream game developer who creates indie games in his spare time; Station 38 is a level-based puzzle game based on the "power and direction" mechanic, but in an unusual way. The mechanic is normally used for things like golf or bowling games, but here it is used in a sort of platformer; each level, you must get a little LEM-like space vehicle from its starting location to a "teleporter" exit. You press LMB and drag the mouse to indicate the direction in which the LEM will launch; a longer line indicates more power. Typically, there are obstacles in the level's geography you must get over and around; sometimes, in fact, a single 'launch' won't do it, but as long as your vehicle has 'power' remaining (indicated by the length of a blue line above it), you can draw another line while in mid-air to alter its trajectory.
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In addition, your vehicle takes 'damage' each time it hits a wall or falls to a platform, more with a faster impact. This is, in fact, the constraint on the level; take too much damage, and your vehicle explodes, requiring you to restart the level.

It's a very simple mechanical system, but well thought out, and with interesting level designs; the original version was quickly developed and somewhat uneven, but Kemp has recently released a more balanced version.