My favorite song using synthesizer is Pink Floyd's "Welcome to the Machine". For the most part I prefer actual honest-to-goodness instruments. But Pink Floyd used synthesizers masterfully to enhance their music; to add to the instruments, not to replace them.
I don't listen to him too much because there are many other good dubstep artists, but I like Skrillex's song "Right In." Also, Kill the Noise has a lot of songs that have robotic talking in them (Talk to Me, Kill the Noise, and many others).