It is implemented as an online-capable plugin within the open-source BCILAB (EEGLAB) framework. 
BCILAB
It is implemented as an online-capable plugin within the open-source BCILAB (EEGLAB) framework. 
EEGLAB
This study describes an optimized online recursive ICA algorithm (ORICA), with online recursive least squares (RLS) whitening, for blind source separation of high-density EEG data. 
RLS