You have full flash in a browser.. that does a lot of what probably 90ish percent of the "iphone" apps provide. You hit some very specific points, IE: map/navigation, that are known weaknesses with the N900 and should have been known before spending that kind of money.

There is a good amount of useful apps in the repos... ask your iPhone buddies to play Quake on your TV, or listen to pandora through your car without an adapter or cables.

Go to pretty much any flash-based website.. or stream a local radio station through the browser.

There are several threads around here about how to "show up" iphone users if that's your thing. I personally don't see much point in it: You either like the device and what it offers you (control, flexibility) or you don't. If you wanted an iPhone that's probably what you should have went for.