Agentless Backup is Not a Myth
Performance is exactly the same as a laptop with a comparable specification but that's not strictly relevant here. The Radeon X1400 graphics run at 445MHz core and 675MHz memory and just about have enough grunt to run games, as indicated by the 3DMark05/06 scores. Realistically, though, Shuttle has specified graphics that are the bare minimum to run the Windows Vista Aero interface.

The PCMark05 score was helped by the HDD element as it uses a proper desktop drive while many laptops are held back by the 4,200rpm spin speed that is typically used in mobile drives.

Overall, the Shuttle has the performance of an £800 laptop but the key point is that the X100 is near-silent in operation. This makes it ideal for use in the living room, or anywhere that you want to avoid a noisy PC. Let's face it, many laptops are fairly rowdy when the cooling fan kicks in.
Value for money is a bit of a vexed question as you can easily buy a laptop with this specification for a lower price and that will include a screen, mouse, keyboard and battery. Shuttle includes Nero 6 suite and a stereo edition of Cyberlink PowerDVD 6, which adds very little to the overall value. Despite that I still like the X100. It's stylish, quiet and has enough power on offer for a day-to-day PC.
Verdict
The Shuttle X100 is an unusual Windows PC that stands out thanks to its tiny size and stylish looks. It thoroughly deserves to reclaim the many receptionists' desks that are currently occupied by iMacs across the nation and it's ideal for duties in your living room where a noisy beige tower simply won't be tolerated. ®

Shuttle XPC mini X100HA
COMMENTS
Overpriced
The Shuttle X100 is overpriced. Compare to the Apple Mac Mini or even the lowest end iMac. I found the low end Core Duo version of the X100 on newegg recently for $1049. However, I can get a Mac Mini for under $600 (smaller HD though) or for the same money I can get an iMac which has a 17" LCD monitor and includes lots of great MacOS software and has the capability of running WindowsXP. Why would I pay the same amount for the Shuttle? Answer is... I won't.
Just hope it doesn't fail on you
No matter how good it is, just hope it doesn't break. Unlike other manufacturers I've dealt with, to get anything fixed or replaced it requires sending the unit back to Shuttle and waiting about a month or more to get it back. If you want a part shipped to you before you ship the old part back, you have to pay a service charge. In all cases you have to pay the shipping to them.
Tiny Pictures
You say that the pictures won't do it's size justice, so why not include a picture of it beside a 17" TFT and standard keyboard and mouse? Maybe even an El Reg coffee mug... Then we'd have a real world idea of how small it is.

IT infrastructure monitoring strategies
Agentless Backup is Not a Myth
Top 10 SIEM implementer’s checklist
Steps to Take Before Choosing a Business Continuity Partner
Enabling efficient data center monitoring