These demo's are official Sony releases of some of the best
PSP games available.
PSP Demo Download Instructions (using a PC):
1) DOWLOADING -
simply download the PSP Demo you wish to play onto your desktop (you can download it elsewhere but it is easier to find on the desktop).
2) EXTRACTING -
right click the zip file and choose 'Extract All...' to bring up the Extraction Wizard (built into Windows XP and Vista). Click the 'Extract' button and after a few seconds a new window will popup with a single folder in it and should have 4 letters followed by 5 numbers such as 'UCJS10036' ... some demos have a suffix such as '-1' or '-demo', don't delete they are important. This is the demo's folder you need to copy onto the PSP's memory stick. Right click this folder and select 'Copy'. 3) TRANSFERRING -
the easiest way is hooking the PSP up to the PC via USB. Once the PSP is detected you usually see a popup asking what you want to do, select "Open folder to view files" which will open a window which has your PSP's folders listed. Open the PSP folder ... then open the GAME folder. This is the location you want to copy the demo's folder. Right click on a blank area of this window and select 'Paste'. After a few seconds of transfering the demo folder (files are contained) you are ready to disconnect your PSP and play the demo.
KEY TO REGION CODING:
(U) - US REGION DEMO
(E) - EUROPEAN RELEASE DEMO
(J) - JAPAN RELEASE DEMO
The Games:
Airport Hero NaHa
Requires Firmware 3.40 and up - (J)
Airport Hero Narita
Requires Firmware 3.40 and up - (J) Ape Academy 2
Requires Firmware 2.81 and up - (E)
Ape Escape Racing
Requires Firmware 2.82 and up - (J) Ape Escape: Saru Saru
Requires Firmware 3.50 and up - (J)
Blokus Club Portable
Requires Firmware 2.81 and up - (J) Bounty Hounds
Requires Firmware 2.80 and up - (J)
Brain Trainer Portable 2
Requires Firmware 3.40 and up - (J) Computer Science Lab 1
Requires Firmware 3.40 and up - (J) Computer Science Lab 2
Requires Firmware 3.40 and up - (J)
DJ Max Portable 2
Requires Firmware 3.11 and up - (J) Doko: Let's Gakkou!
Requires Firmware 3.40 and up - (J) 
Dungeon Explorer
Requires Firmware 3.51 and up Eiyuu Densetsu
Requires Firmware 3.40 and up - (J)
Exit 2
Requires Firmware 2.81 and up - (J)
Full Auto 2
Requires Firmware 3.40 and up - (U) Go! Sudoku
Requires Firmware 2.71 and up - (J)