This is a truly comprehensive set of test problems (some quite challenging), assembled by Professor Floudas of Princeton University, one of the maestros of formal mathematical optimization. Many of the problems are sure bets to defeat most home-grown codes, I think.
Megan Hart
John Cooke
Moshe Nehmad
Julia Copus
Robert Anderson
Sara Blaedel
Princeton Review
Wemdy Dolber
Rajaa Alsanea
Hasani Pettiford
Robert J. Peroni
Rachel Elliot
Tikva Frymer-Kensky
Janice M. Ladendorf
Camille L.Z. Blachowicz
Paul Hillyard
Kay Arthur
Edward Friedman
Veronika Martenova Charles
Fiona Robyn
Jenni Fleetwood
Laura King
Marco Staake
P.T. McHugh
Shelley Gaskin
Alexandre Dumas
Alex Raynham
Chris MaGee
Princeton Review
Sue Mongredien
Keith W. Harvey
Tracey Delio
U. C. (Uday Chand) De
Carlton Wallace
Michael Hollington
American Medical Association
John Burnett
Joseph Ziegler
Christine Bell
Richard L. Hamm
Allegra McEvedy
Maureen Anderson