cache some database tables (updated at some interval) 
reuse/cache database statement handles
code tiding/consistency
volume handling for instance placement
file creation retrying
server config file
make Apache::DBI behave
WSDL
split SOAP out of Client.pm
error string support

distant future
--
volume size/% in-use discovery
server side per client lock tracking
client side lookup table of filehandles/locks
Perl only?, scoped lock release/filehandle destruction
