Lets do a little review:
Sub-2000 PCCs: One of fairly few PCCs on the market. Takes common inexpensive handgun magazines. Fold up fairly compact for transport/backpacking. Considered one of the best camp guns on the market because of this. Highly desired, virtually impossible to find, especially in glock mag versions.
SU-16 family: One of fairly few semi-auto .223s that isn't a mini-14 or AR. Uses Ar magazines. Folds down for easy transport, one variant even can fire while folded. uses several ar-15 components. Inexpensive compared to other .223 semi-autos, EXTREMELY lightweight. Hard to find, generally doesn't stay in stock long. Note: Family includes one of very very few factory SRBs on the market.
RFB: When it came out it was the only .308 bullpup on the market. Considered to have one of the best triggers of any bullpup. Shorter than a folded FAL-paratrooper version. Available in 3 barrel lenghts, though good luck finding any of them. Same weight as the IWI Tavor, which only comes in .223. Uses commonly available FAL magazines. One of the most desired and hard to find rifles in the country.
PF-9: one of the smallest 9mms available. Has inspired several clones and knockoffs. Rumor has it that the Ruger LC9 is a clone of this gun. (I have no idea if this is true or not.)
p-11: One of the smallest double stack 9mms available. Also having inspired clones and knockoffs. In fact, the SCCY CPX-1 is almost a straight clone of this, from a former Kel-Tec employee.
PMR-30: (and I suppose its grand-daddy the grendel p-30) An ultra-light, full size .22wmr handgun with 30 round magazines. Excellent sights out of the box. Considered to be >THE< hardest to find and one of the most desirable current production handguns. See my review in the OP for my opinion.
KSG: While it isn't exactly a clone of the neostead, it is obviously inspired by it. Twin tube pump action shotgun. It incorporates features that bypass California's magazine capacity ban (and those cropping up in other states) As with many of the above, it is considered very highly desirable, and very hard to find. Kel-tec has stated that they're expanding their production on the KSG as a priority over everything else currently.