Anything interesting you can do with an otherwise unused op amp?

[EBK]

I recently designed a couple circuits that happen to require 3 op amps, but I elected to use TL074s for both designs.  I've properly terminated the unused op amp in each layout, but it seems somehow wasteful to not utilize the entire quad package.  So, I was wondering if anyone had any interesting ideas for how to put an otherwise unused op amp to use.  All suggestions, from serious to outright wacky would be appreciated.  Thanks!

[bluebunny]

Make a nice stable V_REF out of it (assuming you need a V_REF).

[nocentelli]

Active tonestack, e.g baxandall.

[GibsonGM]

Input buffer?

[antonis]

Input buffer?

Only if there is an inverting input with a low value Rg.. 

P.S.
Just playing the smart guy, Sir ..

[slacker]

Phase inverter,  wet/dry or clean/dirty blender/mixer , rectifier for octave up.

[R.G.]

Tunable resonance or notch filter to add some really noticeable voicing.

[Ben Lyman]

...recently designed a couple circuits...

Yes, but what are they?
Is it a mixer with active EQ, buffered input, phase inverter and a tunable notch filter? 

[EBK]

I intentionally left out the details of what my original circuits were because I'm seeking to improve my mind rather than improve those specific circuits.   

Great suggestions, all! 

[rutabaga bob]

Since no one else has said it: welcome to the forum!

[GibsonGM]

Input buffer?

Only if there is an inverting input with a low value Rg.. 

P.S.
Just playing the smart guy, Sir ..

Depends on what your input impedance requirement is!!     LOL     My LP is pretty 'sharp', and actually sounds better with some tone suck, like a wah, first in the chain....

[EBK]

Since no one else has said it: welcome to the forum!

Thanks!  Long time lurker, first time poster.