ScummVM is a program which allows you to run certain classic graphical point-and-click adventure games, provided you already have their data files. The clever part about this: ScummVM just replaces the executables shipped with the games, allowing you to play them on systems for which they were never designed!
ScummVM supports many adventure games, including LucasArts SCUMM games (such as Monkey Island 1-3, Day of the Tentacle, Sam & Max, ...), many of Sierra's AGI and SCI games (such as King's Quest 1-6, Space Quest 1-5, ...), Discworld 1 and 2, Simon the Sorcerer 1 and 2,Beneath A Steel Sky, Lure of the Temptress, Broken Sword 1 and 2, Flight of the Amazon Queen, Gobliiins 1-3, The Legend of Kyrandia 1-3, many of Humongous Entertainment's children's SCUMM games (including Freddi Fish and Putt Putt games) and many more.
You can find a full list with details on which games are supported and how well on the compatibility page. ScummVM is continually improving, so check back often. Among the systems on which you can play those games are Windows, Linux, Mac OS X, Dreamcast, PocketPC, PalmOS, AmigaOS, BeOS, OS/2, PSP, PS2, SymbianOS and many more...
You can download Scummvm here pick the one for the PSP as there are many versions currently available.
Although it is possible to download games from ROM sites, Scummvm has several freeware games available for download HERE
Now to install Scummvm and how to use it. I had to check a bunch of sites as many had conflicting information due to the various versions of Scummvm and Custom firmware. I can confirm what is said in the video below works and that is how installed it.
