This is a running version of the example Carlos Bueno uses in his A List Apart article to illustrate "accent-folding" in AutoComplete. The example uses YUI 2's AutoComplete Control and Carlos's accent-folding script.
There are four address-book entries in this autocomplete field:
Type lo into the field and note how Carlos's pattern-matching function picks out all logical matches — not just those that are a literal unicode match for that string.