Older books:
Numerical Solution of Partial Differential Equations by the Finite Element Method (reprinted by Dover 2008)
Computational Differential Equations (1996)

Recent books:
Applied Mathematics Body & Soul I-III (2003)
(Vol I) (Vol II) (Vol III)

Dreams of Calculus: Perspectives on Mathematics Education (2004)

New book:
Computational Turbulent Incompressible Flow
(prel version for download) (2007)

Books under production:
Computational Thermodynamics
Many-Minds Relativity with Many-Minds Quantum Mechanics
Computational Black Body Radiation
The Clock and the Arrow: A Brief Theory of Time
The Secret of Flight
The Secret of Sailing