I got it from clickykeyboards.com. This is the listing for the very keyboard I ordered:
http://www.clickykeyboards.com/index.cfm/fa/items.main/parentcat/12675/subcatid/0/id/309468The photographs in the listing are not of the actual keyboard, but of the same model, the "Options by IBM" version of the M15. The photograph of the "birth certificate," however, with serial number and date of manufacture, is of the very keyboard now in my grubby little hands. Extremely rare item, only the 9th to cross Brandon's way at clickykeyboards.com. I'd been waiting months for one to become available, checked almost every day on eBay and clickykeyboards.com. This one was released for sale on clickykeyboards.com on Friday, November 23, the 13th birthday of this keyboard, according to the bottom label/"birth certificate". I snagged it as soon as I got the chance, at 7:00 AM in the morning PST, right out of bed. These things are so rare that I had no second thoughts about buying it, despite the cost. Cost, you may ask? More than any sane person would reasonably pay for a computer keyboard, but when it comes to keyboards, I have lost hold of my senses.
I know that one of these showed up on eBay around August of 2006, and fetched a high enough sum as to bring a second M15 out of the woodwork. Two for sale in one month. Incredible. And apparently, per Brandon's description, the one in the YouTube video was sold on eBay in February of this year. But that might have been it: 3 eBay listings of the M15 in the past 16-17 months. Even the Touchstream keyboards show up more more frequently than that. And I don't know when the last one prior to this one was sold on clickykeyboards.com. I'm pretty sure not in the last 6 or 7 months. So I'd been waiting a long time for this one.
Are the keys clicky? You bet! They're the buckling springs of the IBM Model M and the various Model M variants. See the
FAQ at clickykeyboards.com for more info and links about buckling springs. These require more force than the Cherry switches to actuate, about the same level of force as the white Alps sliders. They are what
ergocanada.com describes as "High Force / Audible Keyswitches." I have no direct experience of the black Alps sliders, but it sounds like they would have a lighter touch than the buckling springs of the Model M boards.
I find the sound and feel of buckling springs to be more straighforward than the white Alps sliders. The white Alps have, when I have trouble adjusting to their feel after a prolonged absence, what I think of as a wobbly uncertainty (I think Whiskey nailed it when he talked about the horizontal play of the key caps in another topic here). But after the inevitable adjustment each time I return to the Avant Stellar, and when I have worked up a good rhythm, the wobbly uncertainty becomes depth of character, a complexity to the key action which lends a certain richness to the tactile experience. The Model M click feels much simpler, a definite assertive ping. The sound on this Model M15 is a bit tinnier than on the standard Model M's such as the 1391401. The ping of the M15 is higher pitched than the click of the white Alps on the Avant Stellar. To me the Avant Stellar (and the silver-and-black SMK-85 as well) goes "clickety-clack clickety-clack..." Whereas the M15 goes "ping ping ping ..." And both are satisfyingly loud.
I didn't realize until after I had ordered that the keys on the M15 have a lower profile than the standard keys on the regular Model M's. I read somewhere that they use the same keys as the Model M2, the home version Model M. Most of the listings for the Model M2 on clickykeyboards.com say that the keys are non-removable. I'm not clear if this applies to the Model M15 keys as well. Maybe I should email Brandon for clarification on this before I try to pop a key and wreak irreparable harm on this jewel.
I'm typing this on the Model M15 right now, unsplit and flat. And yeah, it makes a terrific space saver keyboard. That hadn't occurred to me when I ordered it. It was only when I placed it beside the Avant Stellar that I realized how compact it was.
Here are a couple of side-by-side comparisons with the Model M 84-key Space Saver:


I had some problems with the NUM LOCK light and the SCROLL LOCK light. I thought it was a defect in my M15. but then I switched the PS/2 to-USB adapter from the expensive Y-mouse back to the much cheaper
Ziotek that I had bought from clickykeyboards.com (also available from Amazon) and everything is working perfectly. (It's sorta funny that there should be a NUM LOCK light but no NUM LOCK key, which is on the companion numerical keypad that is apparently much rarer than this ultra-rare keyboard.)
I want to spend more time with this keyboard, but the thing is, keyboard slut that I am, I've also fallen in love with the non-clicky but mechanical Filco Majestouch, which just may be the most comfortable keyboard I have ever typed on. I'll have to post a follow-up in the Majestouch thread in the next few days.