"When you play in a public sandbox, anyone can copy your castle.
So it was only a matter of time before the commercial Linux vendors
saw even their enterprise-grade wares imitated.
"The Finnish group Lineox released a Red Hat Enterprise Linux
(RHEL) 4 clone on Feb. 25, Pie Box Linux followed with its
iteration three days later, and CentOS released a clone on March 2.
A RHEL 4 clone is also expected from Whitebox Linux sometime soon.
In each case, the groups involved simply downloaded the freely
available Red Hat source code and compiled it, providing a working
RHEL distribution for the cost of bandwidth..."