This plugin for Power Auras Classic adds that functionality. You can assign "actions", which are essentially spells, macros or items to specific auras. When the aura in question is shown, the associated actions will glow on your action bars. And when the aura is hidden, the glows would disappear.

The AddOn was designed to assist in replicating what a lot of players have been asking for; customizable spell alerts. While Power Auras already filled most of this niche with the epic graphics, it didn't make buttons look all pretty. Now it does through this plugin.

Actions can be one of three things, and any aura can have as many actions as it so desires.

Spell - This action type represents a spell on your action bars. You can simply put in the spell name or ID (like Frostbolt) and Frostbolt will look awesome when your aura shows. If you have the spell in a macro, this will also be highlighted.
Macro - If you have a macro that doesn't necessarily cast anything, you can include this too. Simply enter the name or ID of the macro and it'll glow like normal.
Item - Say you don't have a spell or macro on your bars. What else could you possibly have. Items! Same deal here, put in the item name or ID and let us take care of the glowy business for you.

AddOn Compatibility

Power Auras Classic v4
Bartender4
CT_BarMod
Dominos
Blizzard's standard action buttons and built in overlays.

How to configure an action

Open your Power Auras Classic configuration window and select the aura you wish to apply an action to. Click the "Edit" button to open Power Auras effect editor.
To the right of the effect editor is the action configuration window. Click the "Add new action..." row to add a new action.
The new action will be added, by default it is of type "Spell" and has the ID 0. For this example, let's assume we want to make Frostbolt glow when this aura is active. First of all, select the newly created row and a new pane at the bottom should expand with several buttons. Simply edit the "Action ID/Name" text box and place in "Frostbolt", or your chosen spell name without quotes.
Press enter and your spell should be saved. If you enter spells by name, you must have them learned and in your spellbook for this to work. If adding a spell, macro or item by name produces an error then try using the ID number instead.

Power Auras Classic: Buttons