Just in case it helps, the services module can easily output data as a set of <li> elements, which is a fairly common way of handling AJAX responses for auto-complete. That might open up some other options.

From a user's perspective, I really like the "Quicksilver Style" livesearch for jQuery. Have a look at the original version, which was implemented in Prototype. Then have a look at a refactoring done by John Resig.

That style of partial name matching is really useful. To find "European Otter" you could, for instance, type "eot", or "otter", or "euot", or "eurot"... you get the idea. It's useful as a way of enabling the user to create their own ad-hoc species coding system.

That looks quite nice. With regards to this project, the majority of the searching is going to be done on the server side, so if we were to use something like this we'd have to work out a reasonably cost-effective way of evaluating the terms in the database in this way - I guess this would mean coding a function into the database. We should be able to do this with any client-side code, because we just return the right list from the services.