Practical Sampling has released some free Lexicon 960L impulse response samples.
Thanks to Randy Hetherington for providing these files! I have been using them regularly in Logic 8 with Space Designer and they are really great. Of course you cannot customize them as you would when using the actual 960L, but Space Designer has its own set of awesome tools.
The Lexicon 960L impulse response samples are available as freeware from the downloads page.