nukes
spirit landed on mars in 2004. and died there in 2009. its little batteries and solar panels gave out. to their credit, they performed way way way beyond expectations. on the other hand, the voyager twins were launched in 1977. they're nearly blind and mostly deaf. but their little nuclear hearts are still pumping out the power to keep the things going. and we pretty much expect them to keep beating long after they disappear over the horizon of our being able to detect them from here. kinda makes me think we should rethink that whole green technology thing.