We had a requirement from a client whose windows website we were migrating to UNIX that the new site be able to handle mixed case tickers, ie, /pwc, /Pwc, /PWC, /pwC, etc. Using mod_rewrite, it was doable:
# Take any mixed or uppercase ticker and set to lower
RewriteMap lowercase int:tolower
RewriteRule ^(/[A-Z]...?)$ ${lowercase:$1} [R,L]
RewriteRule ^(/.[A-Z]..?)$ ${lowercase:$1} [R,L]
RewriteRule ^(/..[A-Z].?)$ ${lowercase:$1} [R,L]
RewriteRule ^(/...[A-Z])$ ${lowercase:$1} [R,L]
This case conversion will be true for any 3 or 4 char URI with an uppercase letter. (It would probably be better to replace the "." above with [a-zA-Z], as it's likely intended for only chars to replace. Above will transform /a/BB as well, which is probably not desired.)