PSPs make valuable expertise available to employers unable to develop it on their own.

FORBES: How to Use a Payroll Service Provider

Since its launch at the end of 2004, over 52.9 million PSPs have been sold globally, highlighting the importance of the portable entertainment market.

ENGADGET: Sony announces 'snackable' 100MB Minis for PSN Store

" 5 million PSPs have been shipped outside of Europe up to this point, but Sony would like to ship 13 million handhelds "in the year to next March.

ENGADGET: Sony launches the PSP in Europe�� finally

Nevertheless, a spot-check of a Wal-Mart store by journos at the Hollywood Reporter found the discs to be in scant supply, with just a handful stacked haphazardly among the PSPs.

ENGADGET: UMD about to be ditched by Wal-Mart?

So, while most gamers are now enjoying their PSPs and Micros and DSs, we thought we'd take a little trip back and look at some of the handhelds from whence they came before them.

ENGADGET: A Brief History of Handheld Video Games

For now, PSPs are sold just in Japan.

ENGADGET: Switched On: The Slight Before Christmas

The links that Bitcoin-Central, and other exchanges who have also applied to be PSPs, will have to the global banking system will make that much easier as it will become possible to transact with a bitcoin account just like any other bank account.

BBC: Virtual cash exchange becomes bank

It wasn't very extensible, and their whole partership with Microsoft to deliver content to PMCs never really panned out, but today TiVo is expected to announce an enhanced TiVoToGo service, which would allow subscribers to transfer recorded programs directly to their iPods and PSPs.

ENGADGET: TiVoToGo officially supports PSP and iPod

This stirred a deeply (well, not that deeply) buried memory in the hive mind that is Engadget, and we hunted down a Sony ad that's run on Japanese TV recently, which shows popular magician Tomohiro Maeda messing with a couple of PSPs and demonstrating playing a networked game on them with a UMD inserted into only one.

ENGADGET: Multiplayer PSP games with one UMD to be a feature, not a hack?