Tested on Ubuntu 9.04 and GIMP 2.6

Make sure you have WINE installed (it's in the repo's)

Download the attached file and extract it, copy pspi and pspi.exe.so to your GIMP plug-ins folder, mine was (home)/.gimp-2.2/plug-ins

Create an empty folder to store your plugins, I created mine in /.gimp/ps plugins

Start GIMP, you may get an error message but it's ok to ignore it.

Go to filters > Photoshop Plug-in Settings and select the empty folder you created.

Close GIMP and copy your plugins to the folder you created.

I recommend copying one plugin at a time and then testing to make sure you have a fully working plugin directory.

Open GIMP again and the filter(s) you copied should now be in your filters menu.

Thanks for the link man.

Any Ubuntu users might find this useful.