What's not allowed.
Proxy servers
Phishing
Malware
Illegal porn
Providing free hosting
Mail bombers
Anonymous mailers
RapidLeech
IP spoofers
Port scanners
Hivemail
Nph-proxy
lstmrge.cgi
phpShell
FormMail.cgi
FormMail.pl
DOS or DDoS Scripts
CPU or Bandwidth Wasting Scripts
I believe it is $10 yearly for unlimited shared DDoS protected hosting, we of course have some other options though.