Download and install Ubuntu 8.10 AMD64 (or x86_64):

Download 64-bit flash from here.

If you have flashplugin-nonfree installed, now is a good time to remove it as we will be using the labs version:
~$ sudo apt-get remove flashplugin-nonfree
This leaves behind some junk. To remove them:
cd /usr/lib
sudo find . -name "npwrapper.libflashplayer.so" | xargs rm
And now install the plugin:
cp path_to_so_file_you_extracted.so /usr/lib/firefox/plugins
Start firefox and have fun. Pandora.com no longer crashes:

And Hulu.com is working awesome:
