Golomb Rulers - Table of lengths of shortest known Golomb rulers, counts of optimal and near-optimal rulers, and some Fortran programs for dealing with Golomb rulers. - http://researchweb.watson.ibm.com/people/s/shearer/grule.html
Orthogonal Arrays - Lists of orthogonal arrays, difference schemes and experimental design tools maintained by Warren F. Kuhfeld. - http://support.sas.com/techsup/technote/ts723.html
Distributed.net: Project OGR - Describes the computerized effort to prove that the known shortest Golomb rulers (up to 25 marks) are really the shortest, or else find the actual shortest ones. - http://www.distributed.net/ogr/
Mathworld - Golomb Ruler - Description and theory, with references to additional reading. - http://mathworld.wolfram.com/GolombRuler.html
Blocks and Design Applet - Fractional factorial design generator by Marko Boon. - http://www.win.tue.nl/statlab/designApplet.html
Hadamard Matrices - A library of Hadamard matrices maintained by N. J. A. Sloane. - http://www.research.att.com/~njas/hadamard/
Bill Cherowitzo's Hyperoval Page - Hyperovals in Desarguesian Planes and related structures in arbitrary projective planes. - http://www-math.cudenver.edu/~wcherowi/research/hyperoval/hypero.html
SOMA Update - Leonard Soicher reports on new SOMAs, which are generalisations of mutually orthogonal latin squares. - http://www.maths.qmw.ac.uk/~leonard/soma
Small Association Schemes - Tables of homogeneous coherent configurations by A. Hanaki and I. Miyamoto. - http://kissme.shinshu-u.ac.jp/as/
Some Constant Weight Codes - As orbits of AG(2,q), PSL(2,2^f) and PGammaL(2,2^f) by Yves Edel. - http://www.mathi.uni-heidelberg.de/~yves/Matritzen/CWCodes/CWCode.html
Caps in Finite Geometries - Tables and examples in PG(k-1,q) by Yves Edel. - http://www.mathi.uni-heidelberg.de/~yves/Matritzen/CAPs/CAPMatIndex.html
Library of SBIBD - Compiled by Jennifer Seberry. - http://www.uow.edu.au/~jennie/SBIBD.html
La Jolla Covering Repository - A database of good covering designs constructed by Dan Gordon. - http://www.ccrwest.org/cover.html
Ted Spence's Home Page - Classification of Hadamard matrices and designs. - http://www.maths.gla.ac.uk/~es/
StatLib - Designs Archive - With programs and algorithms for creating designs for statistical experiments. - http://lib.stat.cmu.edu/designs/
Handbook of Combinatorial Designs - Home page for The CRC Handbook of Combinatorial Designs. - http://www.emba.uvm.edu/~dinitz/hcd.html
Design Theory Resource Server - A research project founded by the UK Engineering and Physical Sciences Research Council. - http://www.designtheory.org/