I have a P-10, purchased in 1989, I think. It's a .380ACP pistol that holds ten rounds in an internal (read: non-removable) magazine. That makes for a ten-rounder hardly bigger than many .25s and .32ACPs of the time. Took some finishing to get it to work, but it does, and is one of several loaded pieces stashed within my house.
Grendel is the predecessor to the Kel-Tec line, both by the same designer.. can't remember his first name, but the last is Kelgren, I think.
Like that one, there were some others that came out. The P-12 was a version of mine that had a traditional removable magazine, though not a ten-rounder. And, of course, the P-30 you see there.