How to beat spell resistance?

[Arbane the Terrible]

My party's all at 12th level now, which means that everything and its grandmother has spell resistance. Aside from the Spell Penetration feats, what does PF have to make beating spell resistance easier?

[Jiggy]

From a nifty little splatbook called the Pathfinder Society Field Guide, there's a consumable called dweomer's essence. It costs (if memory serves) 500gp, and you use it as a material component when you cast a spell (in addition to whatever other material components the individual spell may require) and thereby gain +5 (again, if memory serves) to overcome SR on that spell.

[RumpinRufus]

Piercing Spell: effectively +5 on SR check
Strand of Prayer Beads (Bead of Karma): +4 caster level
Orange Prism Ioun Stone: +1 caster level

[Fromper]

Varisian Tattoo is a feat that adds +1 CL when casting any spell in a particular school.

[Thomas, the Tiefling Hero!]

It's too late for the OP's party (unless someone dies and is replaced, I suppose), but tiefling clerics have an alternate favored class bonus of +1 to overcome SR of outsiders.

I'm taking it every single level.

[Ravingdork]

Spell Perfection: Doubles many of the above-mentioned bonuses to bypass SR with a single spell. (Only available at 15th-level though.)

[Morain]

Be an elf

[bfobar]

Half Elves get the Feat from ARG Elven Spirit (must take at level 1) that gets you another +2, and since its a feat it doubles with spell perfection, so now they're better than elves IMO for a super SR beating build.

Divination wizards get that bonus d20 roll that you can use to decide if you want to try to blast the enemy directly.

Fey bloodline gets to roll twice to punch through SR.

Basically, don't forget all those powers out there that provide a d20 re-roll.

A half elf divination (foresight) specialist that likes casting flesh to stone should be rolling a
+2 spell penetration
+2 greater Spell penetration
+4 piercing
+2 elven spirit
+1 caster level ioun stone
+2CL spell specialization
+12 base caster level
for a grand total of +25 on your d20 roll which you should have sitting there on the table already from your divination ability. at level 15 that shoots up to +34 +38 if you count piercing spell with spell perfection.
The Tarrasque only has SR 36. No problem. (yes I know he's immune to petrification. Thats the highest SR I know of, thats all.)

Next repeat the same process with your saving throws and piss everybody else at the table off with your Save or Dies.

[Lord Pendragon]

How does your DM feel about spell research? I decided to research this spell for my magus (or plan to research it in a few levels):

Aran's Spellbreach:

Aran's Spellbreach
School abjuration; Level magus 3
CASTING
Casting Time 1 swift action
Components V, S
EFFECT
Range close
Target 1 weapon
Duration 1 round (D)

DESCRIPTION
You imbue one weapon with a powerful magical aura that suppresses spell resistance. Until the end of your next turn, successful attacks reduce the target's SR by 3, up to a total of -12 SR with four successful strikes. This reduction lasts for 1 minute, after which the creature's SR recovers at a rate of 1 point per round.

Obviously this spell is tailored for a magus. But you could research some form of anti-SR for any caster. If your DM is amenable, you could work out something similar.