OpenViBE is a popular platform that allows to acquire data from any compatible EEG device. We just added full support for OpenViBE in EventIDE, which means that you can seamlessly enable real-time monitoring, signal processing and various forms of neurofeedback control in your experiments. No or little efforts are required even for advanced research techniques, such as phase-locked stimulus presentation (see our youtube demo). You can find a full list of supported EEG devices here.
See also our blog post dedicated to signal processing in EventIDE.