Ok i guess as you have tryed mounting all the scsi device names its a kernel driver problem... just in case its not try this...
[dennis@icedesk:~]$ cat /proc/scsi/sg/device_strs PHILIPS CDRW48A P1.3 Generic USB SD Reader 1.00 Generic USB CF Reader 1.01 Generic USB SM Reader 1.02 Generic USB MS Reader 1.03
The SCSI devices are mountable as /dev/sd[abcd]1 for non cd/dvd devices(my cdrw is /dev/scd0). Oh and getting a card reader will only cost £7 from ebuyer(but you still may need to recompile your kernel or use a standard one). Oh maybe you'll need to turn on the kernel opption "probe all LUN's" if the device has more then one "memory" that it allows access to over usb.
- Dennis