Azizah Asgarali reviews the Kaweco Supra fountain pen over at (Gourmet Pens)[http://www.gourmetpens.com]. It comes with a removable extension.
In the collapsed form, the pen is almost too short to use if it's not posted. I'm just going to ignore the comfort (or lack of) comfort in this set up. It works for a quick note, but probably not for those with larger hands. Posted, the pen is well-balanced and feels decent. My favorite conformation is unposted, with the extension in place.