If you really need them spread out evenly, you could take an MD5 hash of the filename and use it as a base for you directory structure... i.e.: 
md/5_hash_value_of_123/123.gif
an/other_md5_have_value/456.gif
ye/t_another_hash_value/789.gif

[download]
Or, You might want to see if the last two digits are "spread out enough" and build a directory structure based on that.... i.e.: 
98/123456789.gif
09/123456790.gif
19/123456791.gif

[download]

-Blake

In reply to Re: brainteaser: splitting up a namespace evenly by blakem
in thread brainteaser: splitting up a namespace evenly by perrin

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