SELinux - Listing Available Contexts

As you know, I've been studying for the RHCE exam. One of the things that I was unsure about with SELinux was how to find all the available contexts. It's easy to find booleans with the 'getsebool' command, but what about a context?
[[email protected] ~]# ls -Z /var/lib/ | grep virt
drwxr-xr-x. root root system_u:object_r:virt_var_lib_t:s0 libvirt

There are TONS of contexts. Today, I found my answer. It's the 'seinfo' command.
[[email protected] ~]# yum provides "*/seinfo"
Loaded plugins: fastestmirror, refresh-packagekit, security
Determining fastest mirrors
epel/metalink | 13 kB 00:00
* base: bay.uchicago.edu
* epel: www.gtlib.gatech.edu
* extras: mirrors.easynews.com
* updates: centosmirror.quintex.com
base | 3.7 kB 00:00
epel | 4.3 kB 00:00
extras | 3.5 kB 00:00
updates | 3.5 kB 00:00
setools-console-3.3.7-4.el6.x86_64 : Policy analysis command-line tools for SELinux
Repo : base
Matched from:
Filename : /usr/bin/seinfo
[[email protected] ~]# yum install setools-console
...
Installed:
setools-console.x86_64 0:3.3.7-4.el6
[[email protected] ~]# seinfo -t | grep samba
samba_secrets_t
samba_unconfined_script_exec_t
samba_net_t
samba_var_t
samba_net_exec_t
samba_net_tmp_t
samba_unconfined_net_t
samba_unconfined_script_t
sambagui_exec_t
samba_share_t
samba_initrc_exec_t
sambagui_t
samba_etc_t
samba_log_t