I have decided to move my hosting site to a Raspberry Pi as a educational attempt to show others that a Raspberry Pi can make a very fast and suitable full platform server that can save a lot of money/resources in power usage.
Live servers running include:
NginX <--Fast memory efficient web server (better than Apache IMO in many cases).
PHP-fastcgi <--(PHP backend)
SSHD <--Allows remote login and file copy.
SAMBA <--Easy access to web folders from windows PCs. +Turns cheap USB HDs into NAS).
FTPD <-- User level file access. (* removed as don't need with SSH)
UnrealIRCd <-- Full IRC chat server.
MYSQL <-- Allows database.
I spent most of my time fine tuning config files for low memory/high performance. The SD card offers slow writes but fast access times (no seek time needed) which you can take advantage of in your config. Total memory used averages around 85+ megs and multi-user performance is very good. No swap file is needed. I'll post some of my config files tomorrow when I have more time. In theory this setup would also run well on a Pi model A with a usb network.
A youtube for my users: http://www.youtube.com/watch?v=SsFq3GnkW9E