Please check that out. I've got nothing to do with the service, but I
believe that this kind of search will become hugely successful in the
Google doesn't support search with words that aren't complete. This
will be a bottleneck for them, if they wish to serve instant
searches. Maybe they could complete the words "behind the scenes" and
perform the search with those guessed / most likely words?
For instance, if the user inputs "itun down", it is close enough to
"itunes download", and the search would "secretly" be performed with
those words instead of what the user actually typed.
Google already knows which words are the most popular, so they
probably could make an educated guess whether "comp" is more likely
to mean a "computer" or a "compass".
I don't know how well this algorithm would perform in practice. It's
just an idea.