This page has instructions on how users of the registered Half-Life can combine the files from the Uplink demo with the normal Half-Life installation to save space and make the Uplink demo act like a Half-Life add-on. Also, Morpheus has cooked up a way for owners of the registered Half-Life to install a variant on the demo after a small four-something MB download. I wanted to make sure this second shortcut was okay with Valve before passing it along, and they just wanted it known there are a few bugs with it (titles don't work, there's some overlapping dialog, that will cause problems that aren't in the demo proper).