Some of my classes have spent some time learning about what NASA does when it comes to launching spacecraft and sending probes around the solar system. One of the great modern technological miracles, at least in my mind, were the Voyager spacecraft launched back in 1977. These both made trips to Jupiter and Saturn, with one then going on via gravity assists to Uranus and Neptune. We are still receiving signals and data from those probes, after moving through billions of miles of space! In fact, a new discovery was made by this mission 30 years after it began, as the solar system is apparently a bit 'squashed.' This means that the solar wind is not circularly symmetric around the boundaries of the solar system, but rather there are 'dents' in the distribution due to varying magnetic fields in the heliosphere of the solar system.
Check out the Voyager project site, and I, for one, cannot get over the images from the mission; truly beautiful. I also highly recommend the Hubble Space Telescope page.