What increases a Wizard's arcane power regeneration?

Arcane power, the resource for the Wizard's non-signature spells generates rapidly on its own, however on Diablo Wiki, it is stated that arcane power

Regeneration over time (can be boosted by items, skills, and passives).

What item attributes, skill and/or passives boost this regeneration?

Here's the comprehensive list based of Blizzard's skill calculator and this list of affixes. No base skills increase Arcane Power regeneration, but many skills have a rune that does so. I've only listed those affecting regeneration, as per your question. Many more runes, etc, reduce the Arcane Power cost of the skills or increase the maximum Arcane Power the Wizard can have:

1. Active skills:

   • Magic Missile (Attunement) - Whenever Magic Missile hits a target you gain 4 Arcane Power.
   • Shock Pulse (Lightning Affinity) - Every target hit by a pulse restores 2 Arcane Power.
   • Spectral Blade (Siphoning Blade) - Every enemy hit grants 1 Arcane Power.
   • Electrocute (Surge of Power) - Gain 1 Arcane Power for every enemy hit by Electrocute.
   • Arcane Torrent (Power Stone) - Every missile hit has a 2% chance to leave behind a Power Stone that grants Arcane Power when picked up.
   • Magic Weapon (Conduit) - Attacks have a chance to restore 1 Arcane Power.
   • Familiar (Arcanot) - While the Familiar is active, you regenerate 2 Arcane Power per second.
   • Energy Armor (Absorption) - You have a chance to gain 4 Arcane Power whenever you are hit by a ranged or melee attack.

    

2. Passive skills:

   • Power Hungry - Gain 30 Arcane Power whenever you are healed by a health globe.
   • Astral Presence - Increases your maximum Arcane Power by 20 and Arcane Power regeneration by 2 per second.
   • Prodigy - When you deal damage with a Signature Spell (Magic Missile, Shock Pulse, Spectral Blade, Electrocute), you gain 4 Arcane Power.

    

3. Item affixes:

   • Foreboding / Ominous on Orb or Wand or Wizard Hat - +Arcane Power on Crit

the templar has a skill learned at level 20 that will increase arcane power regeneration by 0.5 per second. It isn't much, but it gives regen and not at the cost of buying certain items in the auction house or changing your skills.