If you have an Orange Micro Grappler SCSI adapter that went dead when you upgraded to Tiger, and you can't find a firmware update anywhere, you can download and install one of the Advantsys drivers (1.2MB download). Find the drivers in the 'Mac OS X Drivers' folder after the archive expands.
I used the Asc3050 driver, and it worked fine with my Orange Micro 906F; your mileage will certainly vary. Hooray, my scanner works again!
Mac OS X Hints
http://hints.macworld.com/article.php?story=20060112125829298