a highly random selection of vaguely related literature
Finding Moonshine: A Mathematician's Journey Through Symmetry
Marcus du Sautoy, Economist review see also Times Online 
Bulk and boundary $g_2$ factorized Smatrices
N. MacKay, B. Short 

Beta Functions of Orbifold Theories and the Hierarchy Problem
C. Csaki, W. Skiba and J. Terning 

The Octonions
John C. Baez 

On the dimension of a composition algebra
M. Rost 

Ein tensorkategorieller Zugang zum Satz von Hurwitz
(A tensorcategorical approach to Hurwitz's theorem),
Diplomarbeit ETH Zurich (March 1998)
D. Boos 