The makers of the mighty Whammy pedal! To be sure Rage Against The Machine would never have sounded as fresh and funky without that red meanie from Digitech. They didn't stop innovating there however, the Jamman looper and Trio "band in a box" pedals continue to blow minds on stage to this day.
If blowing speakers is more your bag then we can recommend the Bad Monkey distortion, a humble dirt box that has found it's way onto the pedal board of some seriously heavy guitarists.
Digitech have always been a favourite among beginners as well as pros, with RP series multi effects pedals that cram in an incredible number of effects for very little money.