I am playing LocoRoco (Halloween Demo) now on my 2.71 SE B, thanks (IN SO MANY, glorious ways) to Dark_Alex!

^_^(I also made a 1.0 version LocoRoco Original, which might work on earlier firmwares!)

It is pretty easy to do, although it does have six steps. This works with both new demos, so feel free to get both (I did).
>.> Also, I heard rumors that this might work for future demos, but there is no way to prove that.

Step One.
Get Dark_AleX's Decrypter Test here.

Step two.
Get PDP Unpacker here.

Step three.
Using unpacker, unpack all files from the eboot to a single folder (makes things easier). Copy the DATA.PSP file to the root of your psp.

Step four.
Run Dark_AleX's Decriptor, and take the file it creates (DATA_OUT.PSP in the root folder), and rename it to DATA.PSP. put this somewhere you can find it.

Step five.
Get a hex editor (I like this one, get it from here), and open up the file you unpacked called "PARAM.SFO". Look for "2.81" or "2.82", and change it to "2.71" (or your firmware). Save this file.

Step six.
Using the PDP unpacker, choose NEW, then click on the ... buttons and find each part it needs. If you do not have the file it asks for, then you don't need it. (on a side note, you can make your own icons/backgrounds/background music... whee!). Click the SAVE option, and this is your new EBOOT.PBP! Stick it in a folder inside (./psp/game/), and your ready to go!
*Also tested on LocoRoco Halloween Demo, Moto GP, Ridge Racer 2, Mercury Meltdown Demo, World Tour Soccer 2, and Kazuo, all work on a 2.71 SE B PSP*

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Another method suggested by kodan50:
1: Open file in hex editor
2: Change the string that read "2.82" to read "2.00" *(or 1.00)*
3: Save to backup
4: Test on PSP
*Tested on LocoRoco Halloween Demo and Moto GP.*
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Hey, it is not working for my firmware!
:Try changing step 5, so that you input 2.XX for your firmware type.
Hmm.. wonder if we could set it for 1.50... huh. Don't know.

Your Links don't work, idiot!
:Ah, well search Google for the things that failed until I fix the link.
1. Dark_Alex's Decrypter Test (His website is here)
2. "PDP Unpacker"
3. Any Hex Editor, although I liked "Freeware Hex Editor XVI32"

I can't find any demos!
:Well, try these on for size:

Link to Original Moto GP : Moto GP Demo
Link to Original LocoRoco : Halloween Loco Roco

Since several people are posting the modified versions, I am going to go ahead and do it also, for now.
If you have 2.71 or above, please use the 2.71 option.
PLEASE TELL ME IF I NEED TO DELETE THIS.

Hacked to allow 1.0 :: Hacked to allow 2.71
LocoRoco :: LocoRoco 2.71
LocoRoco Halloween :: LocoRoco Halloween 2.71
Moto GP :: Moto GP 2.71
Ridge Racer 2 :: Ridge Racer 2 2.71
Mercury Meltdown :: Mercury Meltdown 2.71
World Tour Soccer 2 :: World Tour Soccer 2 2.71
Kazuo (Sudoku) :: Kazuo 2.71

I tested these on my 2.71 SE B firmware, put them in your (psp/game) folder.
If you DO have 2.71 SE B, feel free to rename the folders. I added a file inside so you can tell em apart.
On a side note, ALL of these will boot (on 1.5, 2.71se) but I am not sure they will run on 1.5.

Early signs show that this works best with American demos.
Jap ones seem to have issues...
^_^ Hope this helps.

I am looking for more demos that work now, and will upload the altered here...
But although I can get them ALL to boot, and even see the intro's, the ones with a lot of jap text seem to fail... I will let you know if I get more to work.
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Once again, THANK YOU DARK_ALEX!
Please give me any other demos you can find, and I will test them and list the ones that work and do not.
^_^ Any advice is welcome.

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