Sk-Perm gives you the freedom to deal with permissions and groups. You can add/remove permissions to/from players as well as groups. You can also add/remove players to/from groups.
This add-on is linked into permission plugins using Vault. Because of this, there are no syntaxes specific to a certain permission plugin, and should work with any permission plugin that is linked into Vault.
This is just the start of something fun. I will add some more to this over the next little while.