iPhone doom is a port from an existing GL port of doom (namely prboom) back to idsoftware and onto the iphone. So yes, someone has done it years ago, and yes, id leveraged that.
There's a good article in Wired UK ish 1 (online at http://www.wired.co.uk/wired-magazine/archive/2009/04/features/the-man-who-saved-the-bbc.aspx) which covers some of the internal culture change that happened around when the iPlayer got revamped and lost its windows-only roots.
We must have been using a different GNUStep.
I'll second that. The n2100 can barely manage 10Mbps in my experience, despite having dual gigE NICs.