Here's my Mammoth clone that a buddy of mine built for me.

Definitely a Muff of some kind. I've been through a ton of them, and currently my favorite is the Pink Flesh.

My old vinyl covered SCOD is the sentimental favorite, although my beat old RAT is what's currently on my board. Depending on which head I'm using, I'll either use the RAT or just the amp.

Woo-hoo, volume.