A new flashy ajax-based directory manager for your site!!!

http://www.ecosmear.com/relay/

PHP Simple Authentication Using MySQL and PHP sessions

This is the easiest script I have found to use for this sort of thing. simple session-based login / register stuff for a MySQL Database and PHP sessions. it's very customisable too.. even has some info on how to adapt it to use MD5 encryption on user passwords... fun eh?

http://simpleauth.munk.me.uk/