brewkit.rb changes ENV destructively, so lets not do that everytime a formula
is required. Now it's possible for other tools to require a formula
description without worrying about side-effects.
Axel tries to accelerate downloads by using multiple connections (possibly to
multiple servers) for one download. Because of its size, it might be very
useful on bootdisks or other small systems as a wget replacement.
Mike McQuaid
Adam Vandenberg
Max Howell
Christian Mayer