You are free to add your own scripts (cgi, PHP) to your webspace (guestbooks, counters, forums, blogs etc etc) provided they do not require SHELL (or SSH) access.
Our PHP Installation has ZEND installed for scripts which require it.
Here is a list of apps which generally we don't allow on our Bronze, Silver, Gold and Platinum Plans. However, if in doubt, ask! As the restrictions are less on our Power Plans 1 and 2.
UltimateBBS (all versions)
Ikonboard (all versions)
Yabb (all versions)
Matt Wright's FormMail v1.90 and earlier
Security Auditing CGIs
Chat room scripts
Network/System Security Auditing Tools
IRC BNCs (PsyBNC, BNC)
IRC Bots (Mech/Eggdrop)
Any SOAP Mailers
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