OptaPlanner - Mathematical optimization software
CoPilot Compare - New car or nearly-new? Compare price savings and features.
Higson.io - Hyperon is a BRMS, that was created with very large decisions and hyper-performance in mind. It stands out with the concept of the business domain which organizes the whole configuration in easy to manage way.
Beepi - Next gen used car marketplace
MiniZinc - MiniZinc is a free and open-source constraint modeling language.
Topmarq - The hassle free way to buy used vehicles privately