[http://www.quarkchess.de/pepito]
Roughly 25.000 lines of C andassembly. Most Interesting aspects are the usage of uninformed searchalgorithms (Negascout) and advanced data structures (B-trees, skip-lists). It playsin the low grandmaster range and can create opening book databases from a pileof thousands of chess games. Technologies: C/C++, WxWidgets.