I've just put up the long-awaited gerbers and better schematics for
balloon 3.21 ('E1') on the site (and split up the confusing mix of
v3.01 and 3.21 files)
http://balloonboard.org/hardware/321/index.html

There are probably mistakes and broken links - do tell if you find them.

The gerbers:
http://balloonboard.org/hardware/321/balloon3v21_gerbers.zip
include a gerbv project loading the 20 most useful layers
so you can easily view them. 

The smart PDF schematic inlcudes components and netlists and overall
layout info so you can find components and connections relatively
painlessly (although this work better in Acrobat than it does in
evince or xpdf currently (which tend not to highlight the right bit)).

Wookey
-- 
Principal hats:  Balloonz - Toby Churchill - Aleph One - Debian
http://wookware.org/