Practical limit to how many items can be in a "folder"?

[Bludd]

Maximum file size
Architecturally: 16 exabytes minus 1 KB (2^64 bytes minus 1 KB)
Implementation: 16 terabytes minus 64 KB (2^44 bytes minus 64 KB)

Maximum volume size
Architecturally: 2^64 clusters minus 1 cluster
Implementation: 256 terabytes minus 64 KB (2^32 clusters minus 1 cluster)

Files per volume
4,294,967,295 (2^32 minus 1 file)

http://technet.microsoft.com/en-us/library/cc781134.aspx

 

[hoom]

Hmm, I did find reference to this bit in my search

If you have a large number of files (300,000 or more) in a folder, and the files have long file names with the same initial characters, the time required to create the files increases. The increase occurs because NTFS bases the short file name on the first six characters of the long file name. In folders with more than 300,000 files, the short file names start to conflict after NTFS uses all of the 8.3 names that are similar to the long file names. Repeated conflicts between a generated short file name and existing short file names cause NTFS to regenerate the short file name from 6 to 8 times.

The command to disable the 8.3 name generation is:
fsutil behavior set disable8dot3 1
(last digit to 0 to re-enable)
Reboot after for it to take effect?
http://technet.microsoft.com/en-us/library/cc753059.aspx

Presumably will break any programs that still use 8.3.

I've tested it out with apparently positive results.
Biggest folders I have are only ~20,000 files though & I did recently upgrade from 2 -> 4GB RAM (W7 x64 beta) so its not exactly a clean test.