Depends on your definition of 'brick' :110: Some kind of hardware failure would obviously require new hardware. If it's just a firmware bricking, the Pandora Battery is probably your best bet. (I'm not sure if this works on the newest versions of the PSP slim though... what version PSP do you have?) Booting the PSP with a Pandora battery starts a 'service mode' of sorts that will allow you to re-flash the firmware from a file on the memory stick no matter what state the firmware chip is in. You do need a working PSP to make a Pandora though...
Yup, it's possible. We've had quite a few PSP repairs in where it just needs reflashing - be it idiots trying to flash their PSP and messing it up, or a legitimate firmware error. My friend sorts them out for us with the Pandora's battery method.
I believe the newer batteries are Pandora-proof....from some reports... There are guides if you know where to look. Also look up Timemachine good luck. EDITED: Yes it does work with new psp slim...you will need Despertar del Cementerio version 4 Time Machine works a bit different in that is booths the FW from memory stick So that even if you can't reflash the psp ..you can still load FW thru ms...thou it will still require Pandora to run it. Ownage.
Take a look: http://uk.codejunkies.com/Products/PSP-MAX-Power-TOOL-SLIM__EF000513.aspx Note that you don't get the software on a memory stick with this, just the battery. You can download the re-flashing software from the internet.
I do believe the Pandora Battery works for all PSP's for un-bricking. I haven't Bricked a PSP yet so I couldn't tell you from experience though.