It finally happened… After experimenting with alternative [firmware] for my WNR3500L router, I uploaded the wrong version and converted the device into a rather expensive paperweight. After some searching, I found thispage, explaining how to revitalize the router by using a USB-TTL converter cable. You can get (e.g. [CP2102 Module Modul USB to TTL Converter)] for a few bucks Ebay, but expect a few weeks for the delivery from China. If you follow the tutorial on the OpenRouters page closely, it should work out quite nicely.