Hello,

After some searching, I found excellent instructions on how to install SketchUp 7.0 under Ubuntu 10.10.
Go to http://fullcirclemagazine.org/2010/03/ and download the e-magazine. On page 16 is the article.
This installs SketchUp 7.0 in such a way that you can save *.skp and *.dae files, something that isn't possible with most of the other methods I've seen.

If I can do it, everybody can do it.
Good luck and happy sketching!

Hans