For the note ext3, on a 32bits kernel:
Q: What is the largest possible size of an ext3 filesystem and of files on ext3?
inspired by Andreas Dilger, suggested by Christian Kujau:
Ext3 can support files up to 1TB. With a 2.4 kernel the filesystem size is limited by the maximal block device size, which is 2TB. In 2.6 the maximum (32-bit CPU) limit is of block devices is 16TB, but ext3 supports only up to 4TB.
For what I know on a 64bits CPU, its posible to go to 16TB without a problem... (personally I don't have the right hardware to test :D), anyway if they were using XFS (not recomended if you dont had a very good UPS and a shutdown script to umount before a crash... ) the max file size is 8 exabytes...
just for the record