The Boss DF 2. I had never heard of this pedal before. Apparently, it's your standard SD 1, but if you hold the pedal down, it simulates feedback. I will be surprised if it's anything like feedback, but it has great potential to generate interesting results. Plus it was apparently a japan-only pedal, so my snob points just got a boost.
It's predigital, so your guess is as good as mine how it's generating/looping the "feedback" tone.
It should be showing up this week sometime, and I'm looking forward to giving it a test toast.
I also own:
Fuzz Factory (fun)
Hairpie (very solid clone of the first series Big Muffs)
Black Big Muff (heavily modded to sound great on bass)
VOX Tonebender reissue (not bad, not great)
Rat (modded to not sound quite so much like ass)
ROSS babyshit brown model (okay, but I've never been as crazy for this pedal as other people are)
SessionMan II (distortion+delay=Framptastic! hilariously fun to play with)
Guyatone HD2 (sounds really interesting, but has no gain, so only useful for non-live applications)
SD-1 (whatever. still better than a Rat)
Danelectro Fab Overdrive (I'm sure I'll find just the perfect overdub to use this on someday)
Snarling Dog Tweed (not that bad, actually - it's flexible and covers the bases from "bluesy growl" to "crunchy" with workmanlike dependability. 2/3rds of your guitarcenter distortion vocabulary covered in one little box.)
Jucifet (a FET gain pedal which is great for what it is)
And my standard rig, which has the rockalizer:
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featuring some compression, a green ringer clone, and a whole lotta gain. And the Brayer:
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Which is a very messed up Octavia copy.