Let the links do the talking:
Quantum of Solace Demo - FileFront.com
FileShack - Download PC Video game patches, videos, betas and trailers for PC, PlayStation, Xbox 360 and Wii
Demo Versions: Quantum of Solace: The Game Demo - Demo Movie Patch Download Section - GamersHell.com
Quantum of Solace Demo Download - FileShack - Download PC Video game patches, videos, betas and trailers for PC, PlayStation, Xbox 360 and Wii

It seems to be 700MB demo with only 5 minutes of gameplay.Didn't get time to download as got the link towards the end of my Night Unlimited download session & none of these site actually make it easy for me to download.

Will download tonight & give you guys a heads up.

NOTE: Fileshack requires registration.