What to do with an ultra-high ECL? [3.PF]

[Sheogoroth]

Let's say, for curiosity's sake that you could beef up your arcane ECL far beyond what it normally should be.
Your actual CL and, by extension, the maximum level of spell you can cast is still restricted.

-Rules-
It has to be arcane.
It can be 3.5 or PF

What, in regards to class, race, feat, etc. is the heftiest bang you can find for your considerable buck?
How do you take advantage of this?

[Studoku]

By ECL, do you mean CL? CL is Caster Level. ECL is Equivalent Character Level and is something different.

As for the question, I've seen builds with a caster level of NI.

[Sheogoroth]

I mean Effective Caster Level, such as appears in this feat: http://www.d20pfsrd.com/feats/3rd-party-feats/kobold-press/general-feats---3rd-party---kobold-press/improved-caster-level

[NoACWarrior]

Ah I read ECL as effective character level haha. Lets explore this first cause its alot more interesting - with a higher ECL you can face epic level monsters which give you tones of loot and EXP while the challange rating wouldn't be so skewed (greater than 7 levels difference = 0 gains)

With a really high CL you could do things like greater magic weapon all day long for +5 on anything and everything.
Conjuration spells which scale off of CL like spiritual weapon or blade of disaster.
Spells which have a high CL cap for damage suddenly do 100s of damage more when put through the metamagic machine.
Area spells which give additional buffs / targets per CL being that much more useful in mass battles.
Greater Dispel magic being very powerful.
Long ranged spells have even more range than they are supposed to.

I won't go into actual builds as I see no reason why current builds can't benefit from the CL increase.