schirra writes: The MIT Game Lab has just released the graphics/physics engine from its popular game "A Slower Speed of Light" as an open-source project, allowing anyone to play around with the effects of special relativity using Unity3D. While the hope is that game developers and educators will use OpenRelativity to develop new kinds of relativistic games and simulations, that shouldn't stop those with a casual interest from playing around with these wicked cool effects. For the physics inclined, these effects include Lorentz contraction, time dilation, Doppler shift, and the searchlight effect--though a PhD in theoretical physics isn't required to enjoy or use the project.
egrep patterns are full regular expressions; it uses a fast deterministic
algorithm that sometimes needs exponential space.
-- unix manuals