I just did this yesterday as a matter of fact. Dropped the alternate install files through Unetbootin to a USB stick and it successfully installed Ubuntu 8.10 on my laptop. So, just wanted to say that it IS possible to do just that.

However, there was no way to install the studio parts. Whenever I tried checking them, the installer said that it couldn't find the packages online, but when I left them out, it didn't have any problems proceeding with the installation.