We search for new variable B-type pulsators in the CoRoT data assembled primarily for planet detection, as part of CoRoT's Additional Programme. We aim to explore the properties of newly discovered B-type pulsators from the uninterrupted CoRoT spacebased photometry and to compare them with those of known members of the beta Cep and slowly pulsating B star (SPB) classes. We developed automated data analysis tools which include algorithms for jump correction, light curve detrending, frequency detection, frequency combination search and frequency and period spacing search. Besides numerous new classical slowly pulsating B stars, we find evidence for a new class of low-amplitude B-type pulsators between the SPB and delta Sct instability strips, with a very broad range of frequencies and low amplitudes, as well as several slowly pulsating B stars with residual excess power at frequencies typically a factor three above their expected g-mode frequencies. The frequency data we obtained for numerous new B-type pulsators represent an appropriate starting point for further theoretical analyses of these stars, once their effective temperature, gravity, rotation velocity and abundances will be derived spectroscopically in the framework of an ongoing FLAMES survey at VLT.