We pride our servers on being an excellent development platform for interactive web sites based upon Perl, PHP and MySQL. Here is the list of Apache Modules which we compile in each of our servers:

mod_throttle, mod_gzip, mod_ssl, mod_php4, mod_perl, mod_frontpage, mod_bandwidth, mod_setenvif, mod_usertrack, mod_headers, mod_expires, mod_auth_db, mod_auth_anon, mod_auth, mod_access, mod_rewrite, mod_alias, mod_userdir, mod_actions, mod_imap, mod_asis, mod_cgi, mod_dir, mod_autoindex, mod_include, mod_info, mod_status, mod_negotiation, mod_mime, mod_log_referer, mod_log_agent, mod_log_config, mod_env, mod_vhost_alias, mod_so, http_core

On our most recently deployed server we run:
core_module authn_file_module authn_default_module authz_host_module authz_groupfile_module authz_user_module authz_default_module auth_basic_module include_module filter_module deflate_module log_config_module logio_module env_module expires_module headers_module usertrack_module unique_id_module setenvif_module version_module proxy_module proxy_connect_module proxy_ftp_module proxy_http_module proxy_scgi_module proxy_ajp_module proxy_balancer_module ssl_module mpm_prefork_module http_module mime_module status_module autoindex_module asis_module info_module suexec_module cgi_module vhost_alias_module negotiation_module dir_module actions_module userdir_module alias_module rewrite_module so_module auth_passthrough_module bwlimited_module frontpage_module bw_module php5_module security2_module

We are not against taking requests from clients to install a particular module. If you need a particular module, we may be able to work something out. However, because this is a shared hosting environment, and changes to the server impact all users of that server, we cannot install any module that might interfere with the operation of any of our other clients' web sites.