I have been searching for worthy applications (apps) for my Nokia 5800 and I've finally found some with good reviews to its functionality.
Contrary to many recommendations of usage of the Garmin maps uploaded to your 5800 at a cost of between 60 - 120, I believe its much better to just buy the original software rather than rely on illegal uploads. Why pay for the original, you might ask. Well, some illegal uploads would cause the app to revert back to default after 1 month usage and require you to either bring the unit back to the uploader or do without altogether.
I'm happy using Nokia/Ovi Maps with Southeast Asia & City explorer license (paid subscriptions). I read the next installment of the Nokia 5800 would be a 5800 Navigation Edition package with Ovi Maps with City explorer of your region. Now that's something to look forward to.
Just installed an application called Qik. Now in the process of streaming videos :)
Nokia 5800 stream