i assume your linux knowledge is good. one of the first things is to be calm... (you knew that)

well... have a read at http://wiki.meego.com/ARM/N900/Using_Rescue_Initrd

Once you understand everything there, see if you can't be helped. Actually, you're better off reading all of the N900 specific stuff on that whole wiki.

From #maemo on Freenode, it seems the Rescue Initrd is very limited... so I'd advise that you try to back up the whole disk on your pc first, before you try to manipulate any data.

Of course, you know the battery can't be charged in this state, so better try and get it charged elsewhere first.

Best wishes