A quick check that can be done immediately after the drop is to make sure that all your device memory is all present and correct by going to "Settings" -> "Memory". If you want more info tap "Details" on "Nokia N900" and check the Total Size. If it reads 27.22 GB then it's fine.

It's been known for the EMMC module to become dislodged from the board after the phone has been dropped in some cases.

dont worry.

i dropped my n900 in the bathroom, while i was standing. i fell from over 1 meter height. on tiles.

it has a very small buckle on the frame thats around the screen. thats it.

i also managed to sleep ON the n900. i usually listen to music before sleeping. when i'm done listening, i put it next to the pillow.
well, i once fell asleep WHILE listening, the next morning i woke op, i realized that the headphones are still in my ears. i searched for the phone, but couldnt find it. so i grabbed the headphones cable and "followed" it. turned out the cable led me to my back. i was lying on the device.

luckily, no damage was done, though the screen makes quiet cracking-sounds when i push it on specific locations. nothing dramatic, though.

If you check out this youtube video of a drop test for the N900 http://www.youtube.com/watch?v=vmSw5lHS1kA even if you were on the top of a bunk bed and dropped your N900 onto concrete it should still work but probly be scratched to hell.

Any experience with repairing that?