I tried out Apache::GzipChain for dynamic mod_perl pages (using Apache::Registry), and it was great for reducing the download ime (especially over modem). I am seriously thinking about using it for our production environment. However, some people are concerned about it using up too much resource. Has anyone looked into scalability issues? Would I see significant reduced throughput using GzipChain? Also why don't most sites gzip their pages (do redirect based on browser support)? Thanks.