Speeding up preparing spells?

[Roco]

I know the wizard, and especially the arcanist, have ways to speed up preparing spells (the arcanist has an ability that burns one of their arcane points and you get a spell re-prepared in 1 round!)

Essentially I'm trying to find out if there are ways for any other prepared caster class to get such benefits:

Re-prepare a spell slot that already has a prepared spell in it
Prepare a spell slot faster than 15 minutes (ideally within 1 round or 2 so it can be combat viable)

[Lady Asharah]

Magus at level 4 can "recall" spells cast earlier as a swift action. At level 11 that ability becomes memorizing any spell in your spellbook as a swift action (and recalling previously cast spells becomes easier).

[Mark Hoover 330]

pearl of Power?

[OmniMage]

I know a few.

The Wizard has an arcane discovery, fast study, that allows them to prepare spells as quickly as 1 minute.

The mythic path, Archmage, has several options. The Archmage Arcana, Wild Arcana, allows them to cast any spell on their spell list as a swift action. They don't need to know the spell themselves; they only need it on their spell list. A path ability they can learn is called Rapid Preparation, is basically fast study, except it also allows you to spend a point of mythic power to prepare a spell as a swift action. If you have Wild Arcana, this doesn't do you much good.

In general, wands are supposed to be the items you use if you want to cast many spells quickly. They're the cheapest option available, don't provoke attacks of opportunity, and don't suffer arcane spell failure.

[Melkiador]

The Quick Preparation feat halves preparation times. But that's not as good as the quick study options of the wizard and arcanist.

[blahpers]

Psychic asylum. I had a druid/Pathfinder Savant use this to great effect, leaving his highest-level slots unfilled so as to be chosen at the moment of need. A loremaster would work too, and there's probably some samsaran tomfoolery or other.

[avr]

Magical epiphany is a feat which lets you prepare a spell as a standard action 1/day.

Preferred spell lets you convert any prepared spell to your specialised spell spontaneously. IIRC there's another ability which has the same effect.

If you happen to have enough water handy the sift power of the flotsam subdomain lets you grab a potion or scroll out of it.