Posting is the term, and postable is the way to describe a pen where the cap can be screwed onto (or pushed onto) the other end of the pen.
I'm a fan of the following myself:
Baron (Cost wise, its one of my most successful pens...beautiful, simple elegance, easy to make)
Caballero (Similar to Baron, but has plated threads, and finial caps, compared to the baron's always-black threads and finial cap)
Triton (More fancy, little more expensive, when using harder materials for the blanks you have to be real careful with the fittings as they can push out and crack those materials, sometimes even woods...but if you can resolve those issues, the pens are beautiful!)
Jr. Anthony (Slightly bigger, I like the band and finial cap designs on this one.)
Jr. Milton (Similar to Jr. Anthony size wise, has an engraving design in the fittings that seems very reminiscent of classic pen makers chasing designs...something I really like.)
There are others, but I'd say so far these are probably the top for me. I have a few other Jr. style pens that I haven't made yet. I'd say most of the Jr Series are excellent pens, hard to go wrong with them in general.
Something about the Baron (and Caballero, I suspect, although I haven't tried it with one yet)...it is fairly easy to push out the finial cap, and replace it with something of your own turning. I've been working on that for several different pens here the last couple of weeks. In fact, you can turn your own cap accent band and finial cap, replacing both. I've been using the cutoff block of resin from the same blank used to turn the cap barrel, to turn finial cap and band replacements. The caps are fairly strait forward...just make sure you don't over-turn the tenon. The bands, now, that's a bit trickier...still trying to refine my approach. I thus far have a tendency to accidentally part the replacement band off before I've actually turned the central open diameter the right size, meaning I then have to manually file it down. I have not yet tried to drill that hole yet, I've only turned it, but given my three attempts so far that have resulted in LOTS of manual filing to get that diameter right, I am going to try and find the closest drill bit that will get me there, and see if that solves the problem. In any case, its fun replacing those parts with alternatives, and adds a unique aspect to your pen, something that is often not as easy to do with the other kits (either, because its not as easy to push out the band and finial cap, or just because the native ones are just so darn beautiful to start with!)