If I had to place bets, I'd say the Little Dot phenomenon was driven by both shilling and enthusiasm. I've called Penchum a shill before, and perhaps it's just excessive fanboyism, but it's a fine line, and I think he's crossed it. Here are five the only seven threads he's started in the amp forum:
http://www.head-fi.org/forums/f5/rev...re-amp-284835/
http://www.head-fi.org/forums/f5/rev...lifier-289765/
http://www.head-fi.org/forums/f5/rev...mkivse-266751/
http://www.head-fi.org/forums/f5/rev...re-amp-309855/
http://www.head-fi.org/forums/f5/rev...ifiers-301219/
The other two threads are 1) post pictures of your glowing tubes (featuring his LittleDots) and other other for the Zero amp/dac. Manufacturers pay for sub forums and/or announcements in the mall forum for such promotion. He regularly bumps these threads so that they are frequently together on the front page of this forum. We've all seen this. What new member, checking out this forum wouldn't think the Little Dots are highly regarded, important amps? He also frequents the headphone forum where he posts links to these threads, and/or the Little Dot website. Obsessive posting by Penchum in these threads, coupled with his equally enthusiastic participation on the Little Dot website forum make his actions highly suspect. I've recommended it be looked into, and I still think it should.
I'm not saying Penchum isn't knowledgeable or helpful. Excessive fanboys and/or good shills always are, but let's take a look at the extent of his knowledge. These are his amps from his profile:
Little-Dot LDII++ (Exterior Mods) (Wife took)
Little-Dot MT (LT1364 Opamp) (Daughter took)
Little-Dot MK1 (Portable, LT1364 Opamp)
Little-Dot MKII (6H30PI Power Tube Mod)(Gold Volume Knob)
Little-Dot MKIII (6H30PI Power Tube Mod)(Gold Volume Knob)
Little-Dot MKIVse (6H30PI-DR's, Gold Volume Knob)
Little-Dot MKV (Gold Volume Knob)
ZERO 24 BIT/192KHz DAC/Head Amp/Pre-Amp (Resistor Mod, Alps Pot Mod)
That's fine and dandy, but what is knowledge without reference points? What other amps has he heard with which to make comparisons? Maybe others, but he never mentions them. For those members who read his "these amps are wonderful" posts, do you ever wonder from what level of knowledge or experience he is speaking, or are you taking his words as truth because he sounds like he knows what he's talking about.
So Penchum's fanboyism/shilling is 100% driving the Little Dot phenomenon. The rest comes from the enthusiasm of those who have followed, some as shown in this thread are, for all practical purposes, his disciples. Most are happy with their amps, and most (certainly not all) have little experience with other amps, so any newbie coming in gets the idea that these amps are the best thing going because that's what folks are saying.
Please note that I'm not commenting on the actual amps, their sq or their value. I also think that if you want one, get one, and if you love yours, that's great. I just hope members use their critical intelligence when evaluating the so-called rave reviews. The op wanted to know what was driving the phenomenon, and I think it's pretty clear.