I reflowed my N900 after being dropped. The flash wasn't completely loose as in Durango's case.

If you ever think about it:

Peel off the keymat, store it on a CD jewel case. Can be reused.

Desolder the tiny button cell backup battery (double-layer capacitor). It will get fried by the preheater.

Remove the camera. This is the hardest part if you don't have the official tool.

It's very difficult to remove the border of the cage around the flash chip. I damaged some of its solder pads. Not crucial, though.

I needed four attempts until I was brave enough to apply enough heat for reflowing ;-) Don't push on the chip. Let it flow.

Take care of the tiny static discharge protection chips. They easily fly away or move. Then, you'll have shorts between USB pins and ground.

Now works again since a few months :-))