UO gpSP Kai goes by a few different names – including GameplaySP or gpSP Kai. It emulates GameBoy Advance games on PlayStation Portable. The emulator is based on other similar programs, but it comes with various improvements. For example, it can run almost every game from the ZIP archive, which is a plus. The latest major version came out in 2009 – a few other updates kicked in later, but there is a decent chance the project has been abandoned.
Some of the best games you can emulate include Mario Kart: Super Circuit, Metroid Fusion, Pokemon Emerald and Final Fantasy VI, among many others. ROM images are not included because they are copyrighted – you will have to find them yourself. The emulator can be downloaded and used for free. The developer has mostly focused on accuracy, so games are replicated in the smallest details – no improvements to the actual games.