Seamless user interaction involves developing new modalities like vision, speech, haptics and bio-signals to create multimodal content and increase interactivity beyond what is possible today. While computing power has increased exponentially per Moore's Law, user interaction speed has not kept the same pace and remains a bottleneck. However, within the next 20-30 years, direct brain interfaces could resolve this issue by allowing implicit, multimodal interaction that approaches a singularity with computing systems.