In same sort of space Lpf83. But I have to admit, I'm kind of prowling looking for something to add just for that get something new Gas. I really don't need it 
I do need to confess to having fallen off the wagon just a bit recently with a "minor purchase"... minor in the sense of relative cost, but not minor in sound. Through the Donner website I was able to score a Donner L1 module and the mini keyboard that attaches to the module for $300USD (I had to do it in two separate purchases, module first then apply coupon offer from the module toward the keyboard).
I've always loved the sound of a real SH-101 and none of the soft-synth renditions ever appealed to the tone snob in me, and I wasn't willing to pay what the vintage ones go for, given their limits. This is a very nice alternative I think, given the price -- I don't think the same tone and filter is available in a soft synth.
The module arrived a couple of days ago and I was able to confirm the sound is what I had hoped it would be, so I'm happy with the purchase. They keyboard has not yet arrived (this evening or tomorrow maybe) so I will have a chance to play with it more after it does.
What I like: The sound(!!), the second envelope, the price, the form factor and the fact the module and keyboard can be separated for easier mobility, the immediacy of the sliders, the fact its a cheap synth but doesn't come from the evil monopoly maker of cheap synths, etc.

What I don't like: No ability to save patches.. and that they were unable to replicate the gain characteristic of the noise generator of the SH-101, although the second envelope seems like more than compensation for that and something that is ultimately more useful to me. The build quality is unremarkable but it does the job and is good enough given the price.
Conclusion: I will keep it, I don't have anything else that does this particular type of sound so well.