whoever57 writes: According to Prof Kubiatowicz from University of California, Berkeley, each time an additional book is downloaded to an ereader, the mass of the ereader increases. The effect doesn't really make the devices more difficult to carry: the professor calculates that 4GB of books adds 1e-18g. to the mass — about the mass of a single virus or DNA molecule.
egrep patterns are full regular expressions; it uses a fast deterministic
algorithm that sometimes needs exponential space.
-- unix manuals