Solar Winds: The Escape

In Solar Winds, you are Jake Stone, a bounty hunter who, through several missions, uncovers a secret coalition between the government of your home solar system and a race of unidentified aliens. Upon further investigation, you find out that, in fact, there is more than one solar system involved… And what is really happening is that three easily-provoked races are being held by a more technologically advanced race in a small cluster of solar systems, and kept there by a force field around them. Hyperdrive technology has been sabotaged, and the 'keys', jump points between solar systems, kept secret.

This game was originally shareware. Registration did not unlock any features of this game, but by registering you were given a copy of the sequel.

Source: Wikipedia, "Solar Winds," available under the CC-BY-SA License.